Britain has flatly denied any foreknowledge of a Mossad plan to assassinate a top official of the Palestinian group Hamas, in Dubai, United Arab Emirates, amid angry accusations in Whitehall that Israel is seeking to deflect blame from itself by implicating others.

British government sources dismissed as "nonsense" a report claiming the Israeli secret service had given the U.K.  advanced warning of possible complications arising from the illicit use of British passports in an unspecified "overseas operation" - the murder of the Hamas commander ­Mahmoud al-Mabhouh.

Officials complained of misleading briefing, apparently by pro-Israeli sources, reflected in a report in Friday's Daily Mail, which claimed that the Foreign Office was told, albeit only in general terms, of an impending assassination. The Mail story was widely reported Saturday, both in Israel and across the Arab world.

"Any suggestion that the government knew anything about the murder before it happened is completely untrue, including the use of U.K. passports," insisted a FCO spokesman.

On Thursday David Miliband, the foreign secretary, described the seeming fraudulent use of cloned British passports as "outrageous." Miliband is to meet his Israeli counterpart, ­­Avigdor Lieberman, in Brussels on Monday. No U.K. action is likely until the completion of an investigation by the Serious Organized Crime Agency.