ATLANTA, April 23 (Reuters) - Former U.S. President Jimmy Carter denied on Wednesday that the State Department warned him not to meet with leaders of the Islamist group Hamas before he made a recent trip to the Middle East.

Carter said Hamas' top official Khaled Meshaal told him during meetings in Damascus on Friday and Saturday that Hamas would "accept a Palestinian state on the 1967 borders if approved by Palestinians."

The United States brushed off the comments on Monday, arguing that Hamas' basic stance, which includes a call in its charter for the destruction of Israel, had not changed.

The State Department has said U.S. Assistant Secretary of State David Welch, the top U.S. diplomat for the Middle East, urged Carter not to meet with Hamas, a position restated by Secretary of State Condoleezza Rice, but Carter denied this.

"No one in the State Department or any other department of the U.S. government ever asked him (Carter) to refrain from his recent visit to the Middle East or even suggested that he not meet with Syrian President (Bashar) Assad or leaders of Hamas," said a statement released by the Atlanta-based Carter Center, which speaks on the former president's behalf.

Hamas, which controls Gaza, is viewed as a terrorist organization by the United States, the European Union and Israel.

The Carter Center statement said the former president attempted to call Rice before making the trip and a deputy returned his call since Rice was in Europe.

"They had a very pleasant discussion for about 15 minutes, during which he never made any of the negative or cautionary comments described above. He never talked to anyone else," the Carter Center statement said.

"President Carter has the greatest respect for ... Rice and believes her to be a truthful person. However, perhaps inadvertently, she is continuing to make a statement that is not true," the statement said.

Carter's reference to the 1967 borders spoke of the West Bank and Gaza Strip, which Israel occupied in the 1967 Middle East War, and to a referendum on a peace deal Washington hopes to clinch this year.

Hamas won a 2006 election and briefly formed a unity government with Palestinian President Mahmoud Abbas. It seized control of Gaza from Abbas' secular Fatah faction in fighting in June.

Hamas has refused to accept major conditions laid down by the quartet of Middle East peace mediators. Those nations include the United States, Russia, the United Nations and the European Union. (Editing by Tom Brown and Bill Trott)