Two more British passports have been linked to the assassination team that killed a Hamas militant in Dubai.

Two additional Irish passports were also linked to the killing. Yesterday in Brussels, Foreign Secretary David Miliband held a 45-minute meeting with Israeli Foreign Minister Avigdor Lieberman, to discuss allegations that the death of Hamas’s Mahmoud al-Mabhouh was the work of Mossad agents.

After the talks, Mr Miliband said: “I obviously went through with Mr Lieberman what the importance is of the investigation the prime minister has announced and the importance we attach to Israel's co-operation with that investigation.

“It is very important that people know we continue to take this issue very seriously indeed. There is very real concern across Europe.”

Mr Lieberman had previously told his Irish counterpart Michael Martin that there was no evidence Mossad carried out the murder of a Hamas militant in Dubai.

Spain’s Foreign Minister Miguel Angel Moratinos, whose country currently holds the presidency of the EU, said they were very worried about the forged passports.

He said: "We're extremely concerned that a passport, which is a very rigorous and legal document, can be used in a different manner and for a different purpose."

Shadow Foreign Secretary William Hague attacked Foreign Office Minister Chris Bryant in the Commons over a Mossad source who allegedly told newspapers that MI6 knew that British passports would be used in the killings.

But Mr Bryant said that Dubai police had told British officials three days prior to their announcement that British passports might have been used, and confirmed it just hours before they announced it to the press.