(Updates with request for funds, Snow, Rice)
By Sue Pleming and Tabassum Zakaria
WASHINGTON, May 22 (Reuters) - The United States said on Tuesday it was considering an urgent request from Lebanon for more U.S. military aid to battle Islamist militants and warned Syria against meddling in its neighbor's affairs.
State Department spokesman Sean McCormack said Lebanon's government had asked for the additional funds as fighting intensified in recent days but he declined to name an amount or predict when a decision would be made on the request.
"Right now we are considering a request for additional assistance coming from the Lebanese government. The Lebanese armed forces are engaged in a tough fight against a brutal group of violent extremists," McCormack told reporters.
Over the past year the United States has provided about $40 million in military assistance to Lebanon.
Lebanon's armed forces have been embroiled in three days of fierce fighting with Islamist militants in a Palestinian refugee camp in northern Lebanon.
At least 22 militants, 32 soldiers and 27 civilians have been killed since the army and the militant Islamist group Fatah al-Islam began fighting on Sunday, making it Lebanon's worst internal violence since the 1975-1990 civil war.
The White House warned Syria against interfering in Lebanon and said militants were trying to derail U.N. efforts to set up a tribunal on the February 2005 killing of former Prime Minister Rafik al-Hariri.
But the White House stopped short of linking Syria to the current spate of violence.
"We believe those behind the attacks have two clear goals: to disrupt Lebanon's security and to distract international attention from the effort to establish the special tribunal for Lebanon," White House spokesman Tony Snow said.
"We will not tolerate attempts by Syria, terrorist groups or any others to delay or derail Lebanon's efforts to solidify its sovereignty, or to seek justice in the Hariri case," he said. "We'll press forward in the U.N. Security Council with redoubled efforts."
Snow said he was not aware of any specific request for more equipment or weapons but said the U.S. government had given this kind of support to Lebanon's government when "necessary."
As part of its strategy to bolster moderate leaders in the region, the Bush administration has firmly backed Lebanese Prime Minister Fouad Siniora and U.S. Secretary of State Condoleezza Rice restated that support on Tuesday.
"The Siniora government is fighting against a very tough extremist foe. But Lebanon is doing the right thing to try to protect its population, to assert its sovereignty and so we are very supportive of the Siniora government and what it is trying to do," Rice said.
U.S. military funding over the past year has gone into buying small arms, ammunition, vehicles and equipment repair, as well as military training for Lebanon's forces, said McCormack.
The Bush administration has asked Congress for $280 million in additional military assistance for Lebanon in the latest supplemental funding request for this year which has not yet been passed. The request made this week by Lebanon's government is separate from the supplemental.