Israel said on Wednesday it would ban East Jerusalem Arabs from voting in a Palestinian election next month if militant Islamic group Hamas takes part - a move Palestinian officials said could delay the vote.
Israel allowed Palestinian residents of East Jerusalem to vote in Palestinian Authority elections in 1996 and at the start of the year when they elected Mahmoud Abbas president.
But a spokesman for Prime Minister Ariel Sharon said Israel will not allow voting in Jerusalem for the January 25 poll because Hamas, which calls for Israel's destruction and has spearheaded a suicide bombing campaign, is running for the first time.
"There is no reason whatsoever we should assist a terrorist organisation on the ballot to gain victory. This would be like letting a Trojan horse into our city," spokesman Raanan Gissin said.
Palestinian officials said the election may be delayed if Israel prevents voting by East Jerusalem residents.
"We cannot hold elections anywhere if the Palestinians in Jerusalem are not allowed to vote," said senior Palestinian official Nabil Shaath.
Abbas denounced Israel's decision saying "this is a very dangerous situation", adding that he would "study" the issue.
A Hamas spokesman said the group, which is expected to make a strong showing in the poll, demanded it be held on time. He would not specify whether that position would remain the same if East Jerusalem Palestinians could not vote.