The announcement came after clashes at a girls' school in the small city of Sar, an area where both Shiites and Sunnis live, when students held an anti-government demonstration.
Calls for the march on the Sunni royal family's palace in Riffa have been circulating among the largely Shiite protesters but it is unclear which group is responsible for the plan.
Another rally is expected to go ahead today at Manama's Pearl roundabout, which has become the base for the anti-government movement.
Ali al Aswad, one of 18 Wefaq MPs, said yesterday about the palace march: "We said this is something (that) will increase the sectarian issues here in Bahrain, and we are against this. The seven political societies, they are against this march," said the MP who resigned his seat in parliament to protest against the killing of demonstrators by security forces.
Last night, the February 14 youth movement backed the march, contradicting an earlier statement calling for Wefaq and the prominent Shiite cleric Sheikh Issa Qassem to stop the hardline dissidents Hassan Mushaima and Abdelwahab Hussein from urging protesters in Pearl roundabout to join in.
Thousands of youth are still occupying the roundabout and have launched almost daily marches. They appear increasingly impatient with the government, which has only made a few concessions so far.
While Bahrain's Shiite majority has long said it is discriminated against, the political goals of the protesters are diverse. The bigger and more moderate Wefaq is demanding the resignation of the cabinet and a new constitution under which the government is elected. Others are calling for the complete ouster of the ruling family. Mr Mushaima's Haq and two other groups established a republican movement this week.
Sheikh Mohammed Habib Moqdad, a Shiite cleric seen as close to Mr Mushaima, also called on protesters to cancel the march on the palace, according to Al Wasat newspaper yesterday.
Mr Mushaimaa did not distance himself from the march: "We let all these young people decide if they will go or not. If I'm free I'll go, if I'm busy I won't."
Such tensions led to clashes between parents at the girl's school in Sar. A student said: "During the break we went on a peaceful protest, we gathered, a few girls. Next thing we know a group of naturalised people were let into school and the school door was locked, they had iron and wooden sticks and knives." s
The girls said parents of pro-government students of naturalised Sunni families came to the school armed with clubs. Parents of Shiite students then arrived and clashes broke out.
Bahrain's practice of settling Sunni foreigners serving in its security apparatus is a thorny issue for the Shiite opposition, which views it as an attempt by the Sunni ruling family to change the country's sectarian balance, an accusation the government denies.
It was not clear whether there were any injuries but one witness said he saw an ambulance driving away one girl.
Bahrain has been gripped by the worst unrest since the 1990s after demonstrators took to the streets last month. Demonstrations have been peaceful since the initial clashes during which seven protesters were killed by security forces, but there have been two incidents of fighting between Sunni and Shiite residents since the demonstrations started.
Sunni and Shiite opposition groups have set up a mechanism to jointly defuse tensions should further violence erupt in mixed areas.
The government yesterday issued a warning that demonstrations by activists near government ministries were illegal.
* With reporting by Reuters, Agence France-Presse and Associated Press.