President Barack Obama has described the situation in Syria as "heartbreaking" but said that unilateral US military intervention¹ there would be a mistake.

奥巴马总统形容叙利亚的局势“令人伤心”，称美军单方面的军事干涉将会是个错误。

Mr Obama said President Bashar al-Assad would fall, as other dictators（独裁者） had fallen, but the US would try to achieve this by working to isolate² Syria.

More deadly clashes were reported across Syria on Tuesday.

The international community remains³ divided on how to end violence there.

The UN says more than 7,500 people have died as a result of the violence in Syria over the past 12 months.

McCain's call

In his first news conference of 2012, Mr Obama warned his critics not to forget the cost of war.

He rejected a comparison to Libya, saying Syria was more complicated.

In Libya, where rebels backed by Nato air strikes ousted⁴ longtime leader Col Muammar Gaddafi after an uprising lasting⁵ several months, the US had "the full co-operation of the region," the president said.

"The notion that the way to solve every one of these problems is to deploy⁶ our military, that hasn't been true in the past, and it won't be true now," said Mr Obama.

"We've got to think through what we do through the lens of what's going to be effective - but also through what's critical for US security interests."

On Monday, US Senator John McCain - Mr Obama's opponent in the 2008 presidential election - called for US air strikes against Syrian forces.

Syrian security forces continued shelling rebel-held towns on Tuesday, activists⁷ said, as President Assad vowed⁸ to continue fighting "terrorism".

A boy and five soldiers were reportedly killed as troops launched an assault on the southern town of Herak, a base of the Free Syrian Army (FSA).