DAMASCUS (Reuters) - Syria had no immediate response on Wednesday to an overwhelming U.S. Senate vote to impose economic and diplomatic sanctions on Damascus, which Washington accuses of backing terrorism.

The Syrian foreign ministry did not comment on the move, which also gave U.S. President George W. Bush broad power to waive the penalties. Syrian state-run media were also silent.

But in neighboring Lebanon, the foreign minister said the measure was a "shocking injustice" which showed Israel's influence on U.S. policy.

The United States has accused Damascus of ignoring U.S. requests to crack down on Lebanese and Palestinian militants.

Washington also accuses Syria of occupying Lebanon and turning a blind eye to militants crossing its border to fight U.S. troops in Iraq.

Syria says it is trying to secure its borders.

Syrian political analyst Imad al-Shuaibi, familiar with official thinking, said he did not expect a dramatic response from Damascus. "Syria does not want to push this to an explosion," he told Reuters. "Syria will respond by containing (tensions), by trying not to concentrate on the negative aspects of this law."

But he said relations with Washington -- which once acknowledged Syrian intelligence help against the al Qaeda network blamed for the September 11, 2001 attacks on U.S. cities -- may deteriorate further.

Damascus said last week that Syrian-U.S. relations had reached their lowest point in years.

An air strike last month by U.S. ally Israel on what it called a Palestinian militant camp deep in Syria -- the first by Israel in Syria in three decades -- helped inflame tension with Washington.

The Senate passed the bill 89-4 on Tuesday following similar action last month by the House of Representatives. But the Senate version gives Bush authority to waive all the penalties if he deems it in the national interest.

The House must approve the change before Bush can sign the measure into law.

In Beirut, where Syria has the last word politically, Lebanese Foreign Minister Jean Obeid told reporters the measure showed how U.S. policy was shaped by the demands of Syria's arch-enemy Israel. "The Syria Accountability Act is a shocking injustice which has to do with Israeli influence on U.S. policy," he said. "One would hope that U.S. policy...would influence Israel, but with time it becomes clear that Israel's oppressive, tyrannical policies influence U.S. policies."