WASHINGTON, May 1: The United States may slap sanctions on Syria "very soon" under a law meant to punish Damascus for allegedly supporting terrorism and seeking unconventional weapons, the White House warned on Friday.

"What our goal is, is to make sure that we take steps that will lead to Syria changing its behaviour, and that's why we're moving forward on implementing the Syria Accountability Act," said spokesman Scott McClellan.

"We'll have more to say on that very soon," he told reporters.

A senior administration official said a decision could be announced "in a couple of weeks".

Mr McClellan said Damascus had not soothed concerns about its "harbouring and supporting of terrorism"; about foreign fighters crossing the Syrian border to take on US-led troops in Iraq; about the Syrian military presence in Lebanon; and about Syria's quest for weapons of mass destruction.

"Those concerns need to be addressed, Syria needs to take them seriously and work to address those concerns, but we are going to continue to move forward on the sanctions," Mr McClellan told reporters.

In December, US President George Bush signed the Syria Accountability Act, which aims to punish Syria for alleged ties to terrorists, tacit support for guerillas in Iraq, and alleged efforts to obtain weapons of mass destruction.

The bill demands that Syria end its support for terrorism; halt the development of chemical and biological arms as well as medium- and long-range missiles; and withdraw the roughly 20,000 troops it has deployed in Lebanon.

It also calls on the governments of Lebanon and Syria to "enter into serious unconditional bilateral negotiations" with Israel in order to secure "a full and permanent peace".

And it says Syria must close its borders to any military equipment and anti-US militants bound for Iraq.

The legislation directs the president to prohibit US exports to Syria of weaponry and so-called "dual-use" technology with both civilian and military applications.-AFP