The chaos afflicting the ranks of Bashar Al Assad's adversaries has complex, often overlapping causes but according to opposition members, a focus of the disorder is disagreement over the role of the Muslim Brotherhood. Phil Sands reports
Syrian opposition in disarray over Brotherhood role
Yet in a pointed reminder of the disarray that afflicts the opposition to President Bashar Al Assad, Mr Al Khatib remains nominally in charge of the National Coalition, his future still undecided. Similarly, Mr Hitto has yet to win the endorsement of the the armed wing of the opposition, the Free Syrian Army (FSA) and is not expected to name the ministers of his interim government until next month at the earliest.
The chaos afflicting the ranks of Mr Assad's adversaries has complex, often overlapping causes, with divisions between the secular and the Islamic, between exiles and groups inside Syria and among factions backed by different international powers. But according to members of the opposition, a focus of the disorder is disagreement over the role of the Muslim Brotherhood.
As the best organised and most unified political faction on the rebel side, the Brotherhood has played a central part in the uprising to topple Mr Assad. It is, however, controversial.
Critics of the group say it wields an influence in opposition decision-making circles and critical bureaucracies dealing with weapons and aid supplies that far outweigh its real presence on the street inside Syria.
An independent political analyst in Damascus who closely monitors the coalition said he estimated 65 per cent of the bloc is loyal to the Brotherhood, far higher than the humble 10 per cent the group publicly claims.
"A major concern with the opposition is that everything is happening in the shadows, people are not always who they say they are, they do not openly declare their interests and backers," the analyst said.
"You have people who say they are not allied with any faction but if you look closely, they have links to the Brotherhood. It might be exaggerating to say they are puppets, but there is some real sense of that, of the Brotherhood having proxies working for it," he said.
Last month, the FSA issued a scathing public letter accusing the Muslim Brotherhood - ostensibly its allies - of jeopardising the goals of the revolt with its politicking and of trying to hijack the popular uprising.
FSA commanders also refused to accept Mr Hitto as interim prime minister. They insisted he lacked legitimacy after a meeting in Istanbul on March 18, when a walkout by some in the coalition left him win with just 35 votes out of a possible 63. He is backed by the Brotherhood and, activists say, was a member of the group as a student in Damascus.
The Brotherhood has dismissed those claims, and pointed to the FSA's own tenuous influence over rebel fighters on the ground.
When it began in March 2011, the Syrian uprising was a tale of grassroots activism and the political awakening of long-dormant local communities. It was a decentralised surge of rebellion against a stifling autocratic regime that had ruled the country for decades and violently suppressed dissent.
It remains unclear what level of involvement the Muslim Brotherhood had in those early days - in crude terms, how many protesters it was able to put in the street.
Domestically, Syria has been a political vacuum for decades, with no real opposition allowed by Bashar Al Assad or his father, Hafez. There have been no opinion polls to gauge credibly the Muslim Brotherhood's support.
According to one former member of the group, an influential figure during the Brotherhood's earlier prominence inside Syria during the 1970s, they had little clout.
"Their influence inside when this  uprising began was nothing. After the 1980s they lost all of their influence among ordinary people," the former member, now an elderly man, said.
"I would say the Brotherhood still has little power on the ground. It doesn't exist in any popular form inside Syria to this moment," he said.
The Muslim Brotherhood was devastated after its armed wing, the Fighting Vanguard, led a rebellion against Hafez Al Assad.
It was a gambit that failed to ignite a nationwide rebellion or topple the regime. The elder Al Assad ruthlessly crushed the revolt in 1982, razing much of Hama city and killing between 10,000 and 40,000 people.
The group went into exile and underground, from where it continued, apparently with little effect, to oppose the Assads.
In a bid to regain its political footing and create a broader constituency that would include secular Syrians, it even co-founded the National Salvation Front (NSF), an ill-fated alliance with Abdul Halim Khaddam, a former Syrian vice president who dramatically split from Mr Al Assad in 2005.
The NSF announced its goals were democracy, civil rights, justice and peaceful regime change. With no mention of Islamic law or armed insurgency, it marked a public liberalising of the Muslim Brotherhood's image - a recognition that Syria, with its sectarian and ethnic mixture, must be ruled by consensus, not a crude imposition of certain Islamic mores over the population.
However, with Mr Khaddam loathed by Assad loyalists and opponents alike, as well as by many ordinary Syrians, the NSF collapsed in 2009, unable to gain the trust of the Syrian public.
If that point represented a political nadir for the Muslim Brotherhood, the group has gained popularity since the uprising started in 2011.
Well-organised networks outside of the country - and close relationships with Qatar and Turkey - have enabled it to funnel aid to ordinary Syrians in need and to supply arms to Islamist militants rather than secular fighters, according to rebels. Where other opposition factions have often been ineffectual in all but their rhetoric, the Muslim Brotherhood has been practical and effective.
In this way it has gained relevance, and followers.
"The Muslim Brotherhood was weak, but it's getting much stronger all the time, and it is supporting armed groups that represent the Islamic side," said a Sunni opposition figure from Damascus.
"It's true that some of the FSA commanders are not happy about the role of the Islamist groups but in reality, on the ground, there isn't much division between the fighters, they all work together," he said.
A member of the Muslim Brotherhood inside Syria admitted the group had limited influence in the capital but was powerful in other, less cosmopolitan areas, including Hama, Idlib and rural Aleppo.
"It's true that in Damascus we don't have much support on the ground but elsewhere we do," he said.
He also said major armed rebel factions were allied to the Brotherhood, including Ahrar Al Sham, a Salafist coalition set up by former Islamist political prisoners that holds significant power in Idlib, Hama and Aleppo provinces.
"No one can say we are not present inside Syria," the Brotherhood member said.
It is such links that have caused concern.
Publicly it remains committed to democracy, free elections, justice and equality. But factions such as Ahrar Al Sham have made little secret of their desire to establish a strict Islamic state, setting off alarm bells among the the country's religious minorities, secular Syrians and more moderate Muslims.
Events in Cairo have added to those worries, with many Syrians seeing authoritarian, intolerant behaviour from the Muslim Brotherhood after its rise to power in post-Mubarak Egypt.
Concern over the group's sway inside the Syrian opposition, and the belief it has an unhealthy obsession with gaining power should the regime fall, is shared at top levels of the coalition, according to activists with knowledge of the coalition's inner workings.
Moaz Al Khatib is now said to favour the creation of a small executive committee to lead decision-making, fearing a large interim government would be less nimble and likely to be dominated by Brotherhood sympathisers, enabling it to further cement its hold on the levers of opposition political power.
"This reorganisation plan is not about clipping anyone's wings. It's about fair representation and ensuring no one is dominant. That is the only way to make decisions," said an opposition figure closely involved with the coalition.
"The Muslim Brotherhood is making agreements and partnerships with groups behind the scenes, within the National Coalition. It is almost creating its own private government within a government," he said.
"That is not acceptable. We cannot have groups with their own private armies or aid networks, it should all come under a united National Coalition and the FSA, which represents all sides of Syria and distributes our collective resources fairly," he said.
"We need everyone in the National Coalition and FSA to commit fully to it or leave. Now is the time for us to work together."