Tony Blair's hopes of keeping Iraq off the election agenda were dashed yesterday by the killing of the 50th British soldier in hostile action since the conflict began two years ago, renewed violence on the streets and accusations from the brother of the murdered British hostage Ken Bigley. Writing in The Independent Paul Bigley claims Jack Straw, the Foreign Secretary, privately urged him to issue a public apology to Mr Blair to avoid criticism of the Government damaging the Prime Minister's bid for a third election victory.