P.J. Crowley, U.S. State Department: "Great concern" over missile claims
A top US official has warned of serious repercussions for Syria if claims that it supplied the Lebanese Islamist group Hezbollah with Scud missiles are true.
Assistant Secretary of State Jeffrey Feltman said "all options are going to be on the table looking at this".
But he declined to say whether the US could confirm a transfer had occurred.
Earlier, Lebanon's prime minister dismissed the accusation, first made by Israel, saying it seemed an attempt to find a pretext for a military strike.
"Threats that Lebanon now has huge missiles are similar to what they used to say about weapons of mass destruction in Iraq," Saad Hariri said. "Israel is trying to reproduce the same scenario for Lebanon."
The United States has shown in the past that we are able to act
Jeffrey Feltman, Assistant Secretary of State for Near Eastern Affairs
Hezbollah fought a 34-day conflict with Israel in 2006 during which more than 1,200 Lebanese people, mostly civilians, were killed. Some 160 Israeli people, most of whom were soldiers, also died.
UN Security Council resolution 1701, which ended the conflict, included an arms embargo on Lebanon, except for transfers authorised by the Lebanese government or UN.
Speaking before the House Foreign Affairs Committee on Wednesday, the state department's top official on the Middle East said it would consider the "full range of tools" available to make Syria reverse any delivery of ballistic missiles to Hezbollah.
Mr Feltman would not confirm that Scuds had been delivered but said it would be an "incendiary, provocative action" if it turned out to be true.
The Syrian embassy has dismissed the allegations that it arms Hezbollah
"The United States has shown in the past that we are able to act," he said. "I expect that all options are going to be on the table looking at this."
The BBC's Kim Ghattas in Washington says the warning does come with an "if", but it is a dire one - this is language usually reserved for Iran and it usually implies that the US would consider military action.
It also underscores the US government's concerns about what could be a volatile situation, our correspondent adds.
Senior US officials have told the BBC they believe Syria has been supplying Hezbollah with more sophisticated weaponry.
Analysts say that if Hezbollah's military wing obtains ballistic missiles with the help of its backers, Syria and Iran, it could potentially alter the military balance in the region, putting all of Israel within reach.
The Syrian government has said the accusations are "fabrications".
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