U.S. Sen. John Kerry has turned over to the U.S. consulate in Jerusalem a letter from Hamas to President Obama that Kerry had received during his trip to the Middle East, FOX News has learned. 

Kerry spokesman Frederick Jones said the Democratic senator was not aware that the letter was from Hamas when he accepted it from a United Nations official, and only heard media reports of its origin, which prompted him to relinquish it.

News that Kerry had given up the letter came after the Israeli embassy and a former Bush adviser on Middle East affairs said Friday that Kerry should not act as mailman for a group labeled as a terrorist organization by the United States. 

The nature and existence of the letter had been in dispute. A United Nations relief agency official first confirmed to FOX News on Thursday that U.N. officials passed on the letter during Kerry's visit to the Middle East.

A State Department official confirmed to FOX News that it was from Hamas and is now under review, though a Hamas spokesman has publicly denied passing on the letter. 

Israeli officials on Friday praised Kerry as a "friend" of the Jewish state, though they had no information on the letter. 

"I do not know that there is a letter, and I do not want to comment on something I do not know even exists," Israel's Ambassador to the U.S., Sallai Meridor, told FOXNews.com earlier Friday. 

But Israeli embassy spokesman Jonathan Peled said Kerry should not deliver any such letter to the president. 

"I doubt whether he would give it to Obama," he said, adding there is no "particular problem" with Kerry accepting the letter.

In question was whether the delivery of such a letter would violate the United States' policy toward Hamas. Obama has said his administration will not engage in diplomatic talks with Hamas unless the group renounces terrorism and affirms Israel's right to exist.

Elliott Abrams, a senior fellow for the Middle East at the Council on Foreign Relations and former Bush adviser, said that such an action by Kerry would have been over the line.

"He should not be accepting a letter from a terrorist group and he should not be serving as a mailman for a terrorist group," he said. 

Kerry, the 2004 Democratic presidential candidate and current chairman of the Senate Foreign Relations Committee, visited the Gaza Strip on Thursday, along with Democratic Reps. Brian Baird of Washington and Keith Ellison of Minnesota, Congress' only Muslim representative. 

The lawmakers were already on a trip to Israel and crossed into the area dominated by Hamas, whose charter calls for the destruction of the Jewish state. Kerry did not meet with anybody from Hamas, according to Peled. 

Peled said Israeli officials had no problem with Kerry's visit to Gaza. 

"He's free to do as he pleases," he said.

Meridor, the Israeli ambassador, called Kerry "a close friend of Israel."

"We wish him great success," he said.

At a press conference in Sderot, Israel, Kerry said the Obama administration's position on Hamas has not changed from the prior administration. He repeated that stance in Gaza. 

"The visit does not indicate any shift whatsoever with respect to Hamas," he said. 

While in Gaza, the U.N. Relief Works Agency took Kerry on a tour of homes destroyed in the recent bombing of Hamas targets by Israeli Defense Forces as well as the American School.

Hamas and Israel have been locked in negotiations brokered by Egypt to secure a permanent truce in Gaza. 

Kerry was scheduled to visit Damascus, Syria, next and meet with President Bashar Assad. Syrian officials have indicated to FOX News in recent weeks that Syria is ready to act as an interlocutor with Hamas to help secure a permanent cease-fire.