The head of the U.N. agency for Palestinian refugees has called on the government to offer additional urgent support following a U.S. decision to cut more than half of its funding.

"In order to keep the schools for 525,000 people open and to keep education and health service going, we need to overcome this financial gap. Otherwise there will be more instability in the Middle East," Pierre Krahenbuhl, commissioner-general of the U.N. Relief and Works Agency, said at a news conference Thursday in Tokyo.

His trip to Japan came after the U.S. government announced on Jan. 16 that it will withhold $65 million from a $125 million aid package for the organization.