"We have sent messages to the Syrians in the past and we will continue to do so," Bush said. "When I said the other day that I expect these countries to honor the political process in Iraq without meddling, I meant it, and hopefully those governments heard what I said."
Bush's remarks were seen as a veiled threat to impose stiffer sanctions on Damascus if cooperation lags on closing the Iraqi-Syrian border to fighters, weapons and money.
In 2003, Congress passed a law requiring the imposition of economic and political sanctions on Syria unless President Bashar Assad certifies that his country has sealed its borders and stopped sponsoring terrorism. Bush imposed the mildest possible sanctions in hopes of persuading Damascus to cooperate but can turn to far more punitive measures.
The Syrian ambassador to the United States, Imad Moustapha, said Syria is doing everything possible to police its border with Iraq but will increase its efforts if the U.S. is dissatisfied.
"While we do not believe there is a huge infiltration problem, even if it is a very small one, we agreed with the [Iraqi] government to work together to address this issue," Moustapha said in a telephone interview.
On relations with Russia, Bush declined to criticize President Vladimir V. Putin for recent anti-democratic moves, such as eliminating the general election of regional governors and increasing state control over the media. He stressed that although the United States and Russia do not see eye to eye on many political matters, the countries have an important mutual security agenda, especially on nuclear issues.
In particular, Bush called for giving Russian inspectors greater access to American nuclear facilities -- a shift in policy that experts described as a "breakthrough" for nuclear security cooperation.
"I think one of the things we need to do is to give the Russians equal access to our sites, our nuclear storage sites, to see what works and what doesn't work, to build confidence between our two governments," Bush said.
The remark appeared to be the first acknowledgment by the administration that the United States, in a confidence-building effort, had permitted Russian officials to visit nuclear sites in Texas, New Mexico and South Carolina in recent months to model the kind of openness they would like to see on the Russian side.
Bill Hoehn, director of the Washington office of the nonpartisan Russian-American Nuclear Security Advisory Council, said that in order to inspect Russian facilities, U.S. officials must be more willing to let Russians inspect American installations.
"This idea has been resisted for a long time by a number of administrations," Hoehn said. "If they are talking seriously about this, it represents something of a breakthrough on the U.S. side."
