Foreign Minister Tzipi Livni says U.S. President-elect Barack Obama shouldn't be talking to Iran just yet.

Her comments marked a first open sign of disagreement with the incoming U.S. administration.

Livni noted that Obama is not willing to accept a nuclear Iran. But in an interview Thursday with Israel Radio, she said "dialogue at this time is liable to convey a sense of weakness."

The U.S. hopes through sanctions to pressure Iran to curb its nuclear program.

Obama has stated a willingness to talk to Iran. He reasons that direct diplomacy with Iranian leaders would give the U.S. more credibility to press for tougher international sanctions.

He's also said he would step up diplomatic pressure on Iran before Israel feels compelled to launch a military strike against Iranian nuclear facilities.