WASHINGTON — The Council on Foreign Relations is rebuffing a suggestion from the Senate’s third-ranking Republican to call off its proposed meeting with the president of Iran.

Senator Santorum, a Republican of Pennsylvania, wrote a letter yesterday to the council’s president, Richard Haass, saying the invitation to President Ahmadinejad demonstrates that the council “draws no distinction between world leaders who deserve respect and those that undermine the very values of the international system the United States seeks to uphold.”

A spokeswoman for the council, Lisa Shields, declined to address the specifics of Mr. Santorum’s letter. “The council has no plans to revoke the invitation to the Iranian president. Richard Haass will respond this week directly to the senator,” she said. Mr. Ahmadinejad, who has questioned the Holocaust and said Israel should be wiped off the map, will meet with members of the council at his hotel in Manhattan tomorrow. On the same day, the Conference of Presidents of Major American Jewish Organizations will host a solidarity rally outside the United Nations to protest Mr. Ahmadinejad’s presence there.

The Iranian leader “does not afford his own people the freedom of speech,” Mr. Santorum wrote. “By allowing him the opportunity to address a public forum in the United States, you are sending the wrong message to the people of Iran.”

Mr. Ahmadinejad is scheduled to address the U.N. General Assembly today. He said last week that Iran offers a better model in the world for global leadership, and requested a public debate with President Bush.

Mr. Bush, who rejected that request on Friday, is expected to ask the United Nations today to take swift action on a resolution to sanction Iran for its continued enrichment of uranium.

As The New York Sun reported yesterday, at least six major Jewish leaders in New York have declined an invitation to meet with Mr. Ahmadinejad.