US President Barack Obama vowed Tuesday not to be deflected from "tough" direct diplomacy with Iran despite the latest anti-Israel tirade by Iranian President Mahmoud Ahmadinejad.

Obama said after holding talks with King Abdullah II of Jordan that the Iranian President''s fiery rhetoric at a United Nations racism conference was "not helpful, it is harmful."

"I think it actually hurts Iran''s position in the world, but we are going to continue to take an approach that tough, direct diplomacy has to be pursued without taking a whole host of options off of the table."

Obama also specifically singled out Iran''s Supreme Leader Ayatollah Ali Khameni as the most important center of power in Iran, in a possible attempt to downplay Ahmadinejad''s capacity to disrupt US engagement plans.

"We will continue to pursue the possibility of improved relations and a resolution to some of the critical issues in which there have been differences, particularly around the nuclear issue," Obama said.

Obama had been asked whether the jailing of US-American journalist Roxana Saberi and Ahmadinejad''s furious rhetoric against US-ally Israel could derail his effort to pursue engagement with the fierce US foe.