President Bush is set to depart later on Tuesday on a week-long trip highlighted by his participation in the Asia-Pacific Economic Cooperation (APEC) summit in Vietnam.
The APEC meetings are intended to focus on economic issues. But experts say they expect North Korea's nuclear program to dominate discussions in side meetings.
Mr. Bush is expected to meet with Russian President Vladimir Putin when he stops for a brief layover in Moscow early Wednesday.
The president is set to arrive Thursday in Singapore where he will deliver a speech that National Security Adviser Stephen Hadley says will establish the tone for the president's trip. Hadley says it will highlight ways the U.S. and Asian countries can work together to face tough challenges.
In Vietnam at the APEC meeting, Mr. Bush is expected to stress the need for greater economic reform and trade liberalization.
The U.S. House of Representatives declined to pass legislation normalizing trade relations with Vietnam Monday evening. The measure fell 32 votes short of the number needed to pass.
Without normal trade relations, the U.S. will be unable to take advantage of liberalized trade with Vietnam anticipated after its admission to the World Trade Organization last week.
The House vote was the first since Democratic gains in last Tuesday's election, but Republicans continue to dominate the current session until the end of the year.