United Nations ? A united Security Council warned a defiant Syria on Monday of possible “further action” if it doesn’t cooperate with a U.N. investigation that has implicated top Syrian officials in the assassination of Lebanon’s former prime minister.

But the United States, France and Britain had to drop the explicit threat of sanctions to win unanimous support for the resolution at a rare meeting of the foreign ministers from most of the council’s 15 members.

The three nations stressed they will press for tough U.N. measures if Syria does not comply with the probe into the killing of Rafik Hariri and others.

Their original resolution threatening sanctions had to be watered down to get all the council members on board. Russia, China, Brazil and others, particularly Algeria, the only Arab nation on the council, strongly opposed putting sanctions on Syria.

Secretary of State Condoleezza Rice said the resolution still left Syria in a corner.

The resolution requires Syria to detain anyone considered a suspect by U.N. investigators and let them determine the location and conditions under which the individual is questioned. It also would freeze assets and impose a travel ban on anyone identified as a suspect.

Syrian Foreign Minister Farouk al-Sharaa, right, speaks with United Nations Secretary- General Kofi Annan at U. N. headquarters on Monday shortly before a Security Council vote.

Those provisions could pose a problem for Syrian President Bashar Assad as well as his brother, Maher Assad, and his brother-in-law, Assef Shawkat, the chief of military intelligence. The Syrian leader refused a request from chief investigator Detlev Mehlis to be interviewed, and investigators also want to question his brother and brother-in-law.

Syrian Foreign Minister Farouk al-Sharaa watched the vote and listened to speeches. He then lashed out at Mehlis and the council for accusing Syria of committing a crime without producing evidence.

He said accusing Syrian security forces of having advance knowledge of Hariri’s killing was tantamount to charging that U.S. officials knew ahead of time about the 9-11 attacks, Spain knew about the 2004 train bombings and Britain knew about this summer’s London bombings.