WASHINGTON (Reuters) -- Worried about possible US aid cuts to the Palestinian Authority, some American Jewish groups find themselves in the peculiar position of defending the funding, particularly money that supports PA security forces.

The US Congress has threatened to review the roughly $500 million in annual aid to the PA if the Palestinians seek full membership at the United Nations, a step opposed by Israel and the United States.

Of the $513.4 million in such aid the Obama administration has requested for the year beginning Oct. 1, $113 million would help strengthen Palestinian Authority security forces and improve rule of law in the West Bank.

Such aid is seen as crucial to reducing violence and to promoting security cooperation between the Palestinian Authority and Israel that could be jeopardized if the Palestinians go forward at the United Nations.

It is difficult for pro-Israel groups to publicly support maintaining aid to the Palestinians given the Palestinians' stated determination to flout the wishes of the United States.

However, at least two groups have explicitly done so -- The Israel Project, which says it has laid out an argument to members of Congress that US security aid should not be cut; and J Street, which has issued a statement defending the aid.

"We have made the case that the security cooperation, which is largely funded and supported by America, needs to continue if we want to see the progress ... in reducing terrorism continue," The Israel Project's president, Jennifer Laszlo Mizrahi, told Reuters, stressing her group does not lobby.

J Street said last week: "We must make clear to American politicians, particularly in Congress, that being pro-Israel does not require cutting aid to the Palestinian Authority in retaliation for approaching the UN

"Such a move will hurt Israel's interests by undermining moderate Palestinian leadership and defunding productive security cooperation."

'The goose that lays the golden eggs'

Elliott Abrams, a former aide to US President George W. Bush now at the Council on Foreign Relations, said "there are grave doubts about significant cuts in aid to the Palestinian Authority" within American Jewish organizations.

"The security assistance case is more obvious because this ... has been in our national interest and it has also helped Israel a good deal," said Abrams, who is to testify on the issue before the House Foreign Affairs Committee on Wednesday.

"But the doubts extend to the nonsecurity aid as well because the question is: what will happen if the PA collapses? Won't that simply create greater and more difficult responsibilities for Israel?" he added.

Other analysts suggested aid cuts could not only undermine security but also the Palestinian Authority itself and Prime Minister Salam Fayyad, who has reformed its governance.

"He's the goose that lays the golden eggs. With no eggs, I don't think he wants to stick around," said David Makovsky of the Washington Institute for Near East Policy think tank. "That means the person who has been the driving force of security cooperation, the driver of institution building, he is gone."

Posturing by Palestinians and by Congress?

There is much anger in Congress toward the Palestinians because of their UN plans but also some recognition that cutting security aid may not be the best policy.

Republican Senator John McCain on Tuesday told reporters he would not favor a "blanket" aid cut-off and he spoke highly of some the security aid being spent on police training facilities in the West Bank.

Senator John Kerry, the Democratic chairman of the Senate Foreign Relations Committee, also said he was skeptical about calls for a cut-off of US aid.

Asked about the possibility of eliminating funding for the Palestinian Authority if the UN votes for Palestinian statehood, Kerry replied: "I'd be very very skeptical about that being the right policy, but it really depends a lot on how that debate unfolds."

Abraham Foxman, national director of the Anti-Defamation League, told Reuters that no one wanted to see security aid to the Palestinian Authority get cut but that he believed the Palestinians should pay a price for ignoring US views.

Foxman suggested the Palestinians and Congress may both be posturing and that it was important to see how things play out at the United Nations as well as after any UN action.

"It may be posturing on both sides," Foxman told Reuters. "But I certainly understand the anger in Congress. You ignore us and then you want us to continue giving you aid?"