RIYADH, 12 September — Saudi Arabia yesterday denounced the “regrettable and inhuman” attacks on the World Trade Center and the Pentagon in the United States, and reiterated its commitment to fight all forms of terrorism.

“Saudi Arabia strongly denounces these kinds of acts, which are against religious values as well as cultural and human norms,” an official Saudi source said. The official conveyed the Kingdom’s sincere condolences to the families of the victims, US President George W. Bush and American people.

Western European leaders broke off their normal business to return to their capitals for crisis meetings and expressed solidarity with the United States. From every corner of Europe, leaders condemned attacks they branded horrendous, abominable, disgusting, monstrous and abhorrent.

The European Union said it was the worst attack on America since Pearl Harbor 60 years ago and was “one of those few days in life that one can actually say will change everything”. “This is an act of war by madmen,” EU External Relations Commissioner Chris Patten said.

Norway called it the worst terrorist attack in history. Russian President Vladimir Putin expressed deep sympathy to the American people “in connection with this terrorist act, this terrible tragedy”.

Kuwait and Qatar yesterday condemned a series of terrorist attacks against key trade and military installations in New York and Washington, offering sympathy to the people of the United States.

“Kuwait, which rejects all forms of terrorism, condemns these terrorist acts and expresses its deep sympathy to the people of the United States,” the Kuwaiti Cabinet said.

In a statement carried by the official KUNA news agency, the Cabinet said it “followed with deep concern the acts of sabotage against key US installations.”

In Doha, Qatari Foreign Minister Sheikh Hamad ibn Jassem Al-Thani condemned “the terrorist attacks and their serious consequences for global security.”

“Qatar condemns terrorism of all forms and whatever its origin,” Sheikh Hamad said, quoted by the official QNA news agency. He expressed his sympathy to the “friendly” American people and offered condolences to the families of the victims.

“France has always condemned terrorism, condemns it without reserve and thinks we must fight terrorism by all means,” President Jacques Chirac said as he broke off a regional tour to rush back to Paris.

British Prime Minister Tony Blair expressed his disgust before racing back to London from a conference. “This mass terrorism is the new evil in our world today. It is perpetrated by fanatics who are utterly indifferent to the sanctity of life,” he said. Queen Elizabeth expressed “total shock”.

“The German people stand by the United States of America at this difficult hour,” Chancellor Gerhard Schroeder wrote in a letter to Bush in which he pledged “unlimited solidarity”. Parliament in Berlin suspended normal business. Air traffic authorities said all flights leaving Europe to the United States had been suspended. Spanish Prime Minister Jose Maria Aznar called the string of attacks a “terrorist frenzy”.

Ordinary people also were horrified. “It’s crazy — and if it’s the US today it’ll be us tomorrow, you can bet. These people are crazy,” said a stunned butcher in Paris.

“I send my condolences, the condolences of the Palestinian people to American President Bush and his government and to the American people for this terrible act,” Palestinian President Yasser Arafat told reporters in Gaza. “We completely condemn this serious operation...We were completely shocked. It’s unbelievable, unbelievable, unbelievable.”

“It’s simply a terrible thing,” he said. “These tragic actions contradict all human and religious values,” Lebanese Prime Minister Rafik Hariri said.

Mexico’s President Vicente Fox said: “We reiterate our total, categorical rejection of all forms of violence, of all forms of terrorism.”

Britain, one of the United States’ closest allies, offered all the help at its disposal to bring the perpetrators to justice. EU leaders said fighting guerrilla attacks would now top the agenda indefinitely.

“It’s certainly going to mean that the fight against international terrorism is going to dominate the international agenda until it’s won,” the EU’s Patten said.

“The international community must respond together to these disgusting acts,” said Italian President Carlo Azeglio Ciampi.

“It is probably the largest attack we have ever seen against an open democracy and therefore an issue for the entire democratic world,” said Sweden’s Prime Minister Goran Persson. “All democratic forces must form a united front.”