The United States likely shared intelligence with Israel leading up to an Israeli air strike in Syria as questions simmer over possible North Korean-Syrian cooperation on a nuclear weapons program, according to a new report.

The Washington Post reported Friday, citing anonymous sources, that the intelligence provided to Israel appears to have corroborated evidence that Israel developed on its own that North Korea was providing some sort of assistance to Syria in developing a nuclear weapons program.

• Click here to read the full report in The Washington Post.

Questions remain, however, over what exactly the evidence was that the United States provided; what evidence the Israelis had to support their claim; what type of collaboration between Syria and North Korea, if any, was taking place; and what exactly Israelis intended to destroy in their Sept. 6 fighter jet attack.

The newspaper reported that U.S. officials were concerned over the allegations, but did not want to play a leading role in the matter because they believed it could seriously endanger its ongoing negotiations on denuclearizing North Korea.

President Bush declined to discuss the issue at his news conference Thursday, but warned North Korea against any efforts at spreading nuclear devices.

"To the extent that they are proliferating, we expect them to stop that proliferation if they want the six-party talks to be successful," Bush said, referring to the ongoing negotiations among the United States, North Korea, South Korea, China, Russia and Japan.

Syria and North Korea have denied any nuclear cooperation.