"And it is a problem that we think Syria needs to act to stop," State Department deputy spokesman Adam Ereli said Tuesday.
Deputy Secretary of State Richard Armitage (search ) is likely to discuss the U.S. complaint when he stops in Damascus on a trip that will take him also to Turkey and Jordan.
Details of Armitage's travels were withheld, except that he would leave Washington later in the week, go to the three countries and return sometime next week.
Syria has shrugged off U.S. complaints, saying it was being made a scapegoat for U.S. failure to stop the uprising in Iraq.
Reports circulated in Damascus, meanwhile, that key support for the insurgents in Iraq was coming from a half brother of Saddam Hussein and Baath Party leaders in the Syrian capital.
Ereli said Syrian officials "have done some things with respect to the border and working with the Iraqis to control the border."
But "the continued presence of former regime elements in Syria who are working, we believe, to the detriment of Iraq and in support of the insurgency is a problem that we think Syria needs to act to stop," he said.
In his travels, Armitage also will convey the importance the Bush administration attaches to Sunni participation in elections scheduled for Jan. 30 in Iraq to select a 275-seat interim assembly.
"That will certainly be a key message," Ereli said.