The agreement includes the provision of simulators, ground and training equipment and spare parts, SPA reported, quoting a Saudi defence ministry official.
The official said the new jets would help qualify Saudi pilots "to use fourth-generation jet fighters in full professionalism and efficiency".
Prince Salman bin Abdul Aziz, the defence minister, visited Britain in April, a major supplier of weapons to the kingdom.
Riyadh in 2006 ordered 72 Eurofighter Typhoons in a deal worth $32.9bn, including armaments and long-term servicing. The multi-role fighter jet is built by a European consortium in which Britain's BAE Systems has a 33 per cent share.
Saudi Arabia spends more than 10 per cent of its gross domestic product on defence.
In September 2010, the Unted States revealed a deal worth up to $60bn to sell F-15 fighters, attack helicopters and other defence equipment and services to the Saudis.
Britain signed in the 1980s its biggest ever arms deal with Saudi Arabia, the long-term Al-Yamamah agreement, which is said to have channelled around 40 billion pounds into Britain's coffers.
The controversial deal was subject to investigation in London over alleged bribes paid to Saudi officials.
Britain's Serious Fraud Office had investigated claims that BAE Systems, one of the world's biggest weapons makers, ran a 60-million-pound slush fund for Saudi officials to attract contracts.
Graft rumours have long swirled around the deal which is a rolling programme of shipments of high-tech military hardware.
But police ditched the probe in 2006, before anyone was prosecuted, after the British government came under pressure from the Saudi government.
Then prime minister Tony Blair defended the decision, which was strongly criticised by anti-corruption campaigners, saying the probe could threaten intelligence links with Saudi Arabia at a key point in the "war on terror."