Government denies tip-off over Hamas Dubai killing as Tories demand answers

The allegation, strongly denied by the Foreign Office, was published in a newspaper report which said that the tip-off was given by a serving member of the Israeli intelligence service Mossad.

He is alleged to have given a warning that an unnamed target was about to be killed and that "a situation" might blow up because those conducting the operation would be carrying UK passports.

Shadow foreign secretary William Hague said he wanted "fuller" answers about when the Foreign Office was aware that fake British passports had been used.

Red notices have been issued via Interpol in the hunt for 11 people allegedly involved in the hit, which was linked to the Israeli secret service Mossad.

Yesterday Mr Hague told BBC Radio 4's Today programme that reports in the Gulf suggested British ministers may have been alerted by Dubai authorities last month, despite claims that they were informed just hours before the news emerged publicly.

"We have had 13 years of the current government and believing at face value immediately everything they say has not been borne out by experience," he said.

"Ministers have been known to suggest that they only knew about something at the last moment that they had known about for some time.

"I'm not suggesting complicity with Israel, I simply say there are news reports in the Gulf that this may have been known about by the British government or other governments at an earlier stage."

David Miliband branded the abuse of ID documents "outrageous" and demanded that Tel Aviv co-operate fully with the UK's investigation.

But after being called in to discuss the situation with officials in London yesterday, Israel's ambassador Ron Prosor flatly denied there was any "additional information" to give.

Tel Aviv's ambassador to Ireland, Zion Evrony, delivered a similarly blank message after an hour of discussions with diplomat David Cooney in Dublin.

Dubai police have revealed that cloned passports belonging to six British Israelis and five Irish citizens were used by a hit squad who allegedly killed Mahmoud al-Mabhouh in the Gulf state last month.

Senior officers say they are "99% certain" that Mossad was behind the murder. Tel Aviv has refused to confirm or deny the link.

Mr Miliband told reporters he wanted to give Israel "every opportunity to share with us what it knows about this incident".

"We hope and expect that they will co-operate fully with the investigation that has been launched by the Prime Minister and will be undertaken by the Serious Organised Crime Agency (Soca)," he said.

Speaking on a visit to the North East, Gordon Brown said: "We have got to know what happened to British passports - it's as simple as that. It's an investigation that has got to take place before any conclusions are drawn."

It is believed the Hamas commander was in Dubai to buy weapons for the militant Palestinian movement when he was killed in a luxury hotel room on January 19.

Dubai police chief General Dahi Khalfan said he was 99% sure Israel was involved. He told the Gulf News: "All elements strongly indicate the involvement of the Mossad."

Soca has confirmed photographs and signatures on the passports used in Dubai do not match those on passports issued by the UK.