Cherie: No 10 steps up the counter-attack Â

Cherie Blair is being invited by the Press Complaints Commission to give evidence to a possible investigation into claims that newspapers have paid money to the convicted fraudster Peter Foster.

The PCC has decided to write to Mrs Blair after remarks by the Labour MP Clive Soley that some papers appeared to have broken their rules by giving sums to Mr Foster. If she decided not to get involved, the commission said, the inquiry could still go ahead, depending on other information it received.

MacLaurin Media, the public relations agency that represents Carole Caplin, Mr Foster's girlfriend and Mrs Blair's lifestyle adviser, said it had strongly recommended she and her partner reject all offers from Fleet Street.

Meanwhile, Mr Foster said he would "tell all" in a statement on Monday.

Downing Street issued a denial that security services or any government officials had been responsible for leaking tapes of Mr Foster's conversations with his mother. The Sun published transcripts of his telephone calls in which he apparently discussed how he could sell his story for £100,000.

Mr Blair avoided questions on the affair during a press conference at the close of the European Union summit in Copenhagen last night. He refused to say what lessons he had learnt from the controversy, telling reporters: "I totally understand why some of you guys will want to concentrate on this. It is for me to run the Government and this is what I am trying to do here." He said such questions could be dealt with at home, and he wanted to concentrate on the very important issues discussed at the summit.

The PCC said it did not usually pursue a "third party" complaint but said that obviously none of the parties involved in a newspaper payment would seek redress. "We have written to [Mrs Blair] to see if there are grounds to take the matter further," a spokeswoman said.