>>>AMMAN, JORDAN -- On the final leg of his Middle East trip, U.S. President Barack Obama and King Abdullah of Jordan discussed the serious impact of Syria's civil war on the region. 

The talks also covered Israel-Palestinian peace efforts. 

Mr. Obama visited Jordan to reaffirm support for the longtime strategic ally of the United States, especially now as Jordan bears the burden of hundreds of thousands of Syrian refugees.

At a joint news conference, King Abdullah said Jordan will not turn refugees away, but needs help with the costs, now $550 million a year and climbing.

The king said, "What we are facing now today obviously is an urgent need for the international community to help in humanitarian assistance to catch up with the challenges we are facing as countries bordering Syria."

King Abdullah said there are now 460,000 refugees in Jordan and the number could double. He said there is a need to increase stockpiling of supplies inside Syria, and aid for those who have fled.

Obama concerned about Syria

President Obama said he is working with Congress to provide $200 million in additional budget support for Jordan.

The talks also covered concerns about prolonged sectarian conflict and what the king called possible "fragmentation" of Syria, with disastrous regional consequences.

Mr. Obama said he is very concerned about Syria becoming "an enclave" for extremist groups, saying that is why the U.S. continues working with partners to support a viable Syrian opposition.

The president said, "Even if we execute our assistance and our coordination and our planning and our support flawlessly, the situation in Syria now is going to be difficult and that is what happens when you have a leader who cares more about clinging to power than they do about holding their country together and looking after their people."

King discusses Assad's future

King Abdullah seemed to backtrack on his offer of asylum for the Syrian leader, saying the question is something that would have be discussed at a higher level by the international community.

The king said, "Obviously from our point of view we are saying we need an inclusive political transition as soon as possible so if the issue of asylum ever came up that is something that I think all of us would have to put our heads together and figure out whether or not if that sort of ends the violence quickly is something worth pursuing."

President Obama was asked about the threat by Iran's spiritual leader Ayatollah Khameini to destroy Israeli cities if military action is taken against its nuclear facilities.

He avoided a direct answer, but said nuclear weapons in the hands of Iran would be a problem for all nations.

Mr. Obama said, "This is not just a problem for Israel, it is not just a problem for the United States, it is a regional and worldwide problem."

King Abdullah said any military conflict with Iran would exacerbate existing problems in the Middle East.

"Any military action at the moment, whether Israeli or Iranian, to me at this stage is Pandora box because no one can guarantee what the outcome will be," said the king.  "So hopefully there is another way of resolving this problem.  At a time of so much instability in the Middle East we just don't need another thing on our shoulders."

Jordan's neighbors continue feud

The two men also discussed Mr. Obama's talks with Israeli and Palestinian leaders. King Abdullah said Jordan is ready to act as a "facilitator" for renewed efforts to re-start direct negotiations for a two state solution.

President Obama said his approach was to listen first and discuss ways to remove roadblocks, acknowledging his approach has been modest because ultimately it is up to the parties to want peace.

Mr. Obama ends his Mideast trip Saturday with a visit to the ancient city of Petra in Jordan before leaving for Washington.