The UK Foreign Secretary Jack Straw today issued a strongly-worded condemnation of the "unlawful killing" by Israeli forces of the spiritual leader of Hamas, Sheikh Ahmed Yassin.
Speaking as he arrived in Brussels for EU talks on new measures to counter international terrorism in the wake of the Madrid train bombs, Mr Straw described the targeted assassination as "unacceptable and unjustified".
Yassin, who Jerusalem accused of being behind the campaign of suicide bomb attacks against Israeli targets, was killed by missiles from a helicopter gunship as he left a mosque in Gaza at daybreak today.
It is feared that his death would lead to a dramatic upsurge in violence in the Middle East, dashing any remaining hopes for the implementation of the US-backed Road Map for peace.
Mr Straw said he did not believe that Israel would benefit from the killing of an old man in a wheelchair.
"All of us understand Israel's need to protect itself - and it is fully entitled to do that - against the terrorism which affects it, within international law," he said.
"But it is not entitled to go in for this kind of unlawful killing and we therefore condemn it. It is unacceptable, it is unjustified and it is very unlikely to achieve its objectives."
Other European Union governments joined the condemnation of Israel for killing the Hamas leader. Several branded the action a violation of international law and a blow to the stalled peace process.
The French Foreign Minister Dominique de Villepin told reporters that France condemned the killing that "amplifies the cycle of violence."
De Villepin said both Palestinians and Israelis must do more to revive the peace process.
"These type of actions do not contribute at all to create the conditions of peace, the conditions of dialogue which are necessary at this moment," EU foreign policy chief Javier Solana said. "This is going to be very, very bad news for the peace process."
The Danish Foreign Minister Per Stig Moeller said the EU has long opposed "extra-judicial killings."
He said that reviving the peace process will not be any "easier when you have killings like that going on in Gaza."
The United States urged both sides to show restraint.
In Washington, State Department spokesman Lou Fintor said officials were in touch with Israeli and Palestinian authorities. "The United States urges all sides to remain calm and exercise restraint," he said.