Up to 13,500 military personnel will contribute to security at the Olympic and Paralympic Games, the Ministry of Defence has revealed.

Reservists will make up 2,100 of the force, after the MoD made an order under the Reserve Forces Act enabling reservists to be called out for permanent service to provide safety and security at the event.

In a Written Ministerial Statement, Defence Secretary Philip Hammond said the reservists would play "an enhanced role".

He said the overall Defence contribution is "on a similar scale" to that deployed by other nations at recent Olympic Games, and will contribute to "ensuring a safe, secure and enjoyable 2012 Olympics".

Mr Hammond will face questions from MPs this afternoon on the Olympics and the security of the Falkland Islands.

The Sun on Sunday will be published for the first time next weekend.

In an email to staff the head of News International, Rupert Murdoch, said that he would be staying in London to "oversee the launch".

The Sun's editor Dominic Mohan welcomed the news, saying it was "a truly historic moment in newspaper publishing".

Every single phone call, email and website visit is to be recorded and kept for a year under new legislation tabled for the next session of Parliament. Security services will also have access to social network site visits under a revised version of plans initially put forward by the Labour government.

The Sun on Sunday will be published for the first time next weekend, News International has announced.

"Next weekend will see the birth of the first ever Sunday edition of your favourite paper," The Sun said.

Rupert Murdoch told staff in an email last week that the new paper would come "very soon," and flew to the UK to oversee the launch.

News International shut down its Sunday paper, the News of the World, amid the phone hacking scandal last year.

Tom Watson has said he will write to the Metropolitan Police Commissioner Bernard Hogan-Howe to ensure any evidence of phone hacking at the offices of the Sun is "secure and safe".

His comments come after ten journalists arrested in connection with hacking were told they could return to work by the paper's owner, Rupert Murdoch.

Mr Murduch also announced that he would be launching a Sunday edition of the Sun in the recent future.

News International will launch The Sun on Sunday "very soon," Rupert Murdoch has revealed.

In a memo sent to all staff of The Sun, Mr Murdoch said it was the company's "duty" to expand "one of the world's most widely read newspapers and reach even more people than ever before."

Mr Murdoch also said News International would "do everything" it could to assist those staff arrested over alleged payments to public officials, and announced all staff suspended over the case were welcome to return to work.

He added, however, that "Illegal activities simply cannot and will not be tolerated at any of our publications."

The company responsible for Olympic ticket sales have been criticised by the London Assembly for their "suspicious" secrecy over the arrangements.

The Assembly's Economy, Culture and Sport committee said Locog, the ticket organisers, have refused several requests to release details of the number of tickets sold at "affordable prices."

Locog previously confirmed that 28% of the 8.8 million Olympic tickets available would cost less than £20, and say they will provide a breakdown of their sales, after the remaining three million Olympic and Paralympic tickets have been sold.

Baroness Dee Doocey, chairwoman of the committee, said Locog's secrecy over the pricing arrangements had "stocked fears" that the most popular events may have a disproportionate number of highly priced tickets.

Speaking to BBC Radio 4, the peer said: "I suspect that in some cases - certainly for the large events such as the opening ceremony, and probably for the 100 metres final – I think, probably, the vast majority of them are not going to go to the public."

Journalists at the Sun are preparing a legal challenge against the unit in News Corporation which gave the names of confidential sources to the police.

The Guardian reports that the journalists have approached the National Union of Journalists to look into the possibility of hiring a top human rights lawyer.

Nine former or current members of the Sun have been arrested as part of the Met Police’s Operation Elvedon, which is looking into illegal payments to the police.

Earlier the UK Supreme Court ruled that it will hear an appeal from Glenn Mulcaire against an order that could have forced him to reveal the names of journalists who commissioned him to hack phones. The hearing will take place on 9-10 May.

News Corporation has revealed some of the Sun and News of the World’s confidential sources on the grounds that they did not deserve protection or because they may have received illegal payments for information. The company’s Management and Standards Committee has been criticised by some at the Sun, after several journalists and sources were arrested in recent weeks.