Japan is getting increasingly worried about whether it will be able to collect some $5 billion in claims against Iraq now that the government of President Saddam Hussein has effectively collapsed.

Japan also hopes to recover about $7.5 billion in losses incurred at the time of the 1991 Persian Gulf War, government sources said.

But collecting the money could prove difficult, given the uncertainty about whether a post-Hussein administration will take on such claims and emerging calls in the United States to cut back on Iraq's foreign debt to help rebuild the war-torn country.