Following the lead of Israel and Canada, the United States will boycott a United Nations racism conference next week because of concerns of anti-Israel and anti-West bias in the meeting's final document, the State Department said Saturday.

The Obama administration had lobbied hard for more format revisions so it could participate, said spokesman Robert Wood.

However, despite improvements, the changes don't go far enough, he added.

Iranian President Mahmoud Ahmadinejad, who has called for Israel's demise, will attend the conference from April 20 to 25.

The concern is the meeting will be hijacked by heated debate over Israel, as it was in 2001.

Canada and Israel had already said they will not attend, while Australia and the European Union are also threatening to boycott the conference.