Democratic presidential candidate Barack Obama met the commander of American troops in eastern Afghanistan on Saturday to talk about the war he says is not getting enough attention from the Bush administration.
Senator Obama's trip, which will also take him to Iraq, Jordan, Israel, Germany, France and Britain, is aimed at proving his foreign policy credentials.
Mr Obama wants to send two more brigades, or about 7,000 US troops, to Afghanistan to shift emphasis from what he calls the Bush administration's "single-minded" focus on Iraq. He has called for a withdrawal of US troops from Iraq in 16 months.
Iraqi Prime Minister Nuri al-Maliki has told German magazine Der Spiegel he supports Mr Obama's proposal, saying he wanted the troops withdrawn as soon as possible. It is the first time he has shown support for Mr Obama's proposed timetable.
The US has about four times more troops in Iraq than the 36,000 it has in Afghanistan. But more of its soldiers were killed in Afghanistan in both May and June than in Iraq.
It is more than six years since US-led and Afghan forces toppled the Taliban for sheltering al Qaeda leaders behind the September 11 attacks, but violence has risen sharply in recent months and there are few signs the insurgency is weakening.
Mr Obama's Republican presidential rival, John McCain, also wants three more brigades in Afghanistan and pledged to find the extra troops by "asking NATO to send more and by sending US troops as they become available."