Republican presidential candidate Ben Carson fired back Friday at the White House for dismissing his claims that China is moving into Syria, saying his sources are clearly better than those of the U.S. government.

Carson said his campaign would release “some material on that” before the end of the weekend when asked about National Security Adviser Susan Rice saying there’s no evidence to support his claims that the Chinese are involved in Syria.

“I have several sources that I’ve got material from, I’m surprised my sources are better than theirs,” he told reporters after a town hall event.

Obama shut down Carson’s “easy” plans to defeat ISIL in a Thursday interview, and said the Republican “doesn’t know much about” the issue.

Carson had floated the theory in rambling response to a question about Middle East policy in Tuesday’s presidential debate.

Watch Carson’s full answer, captured by TPM:

This story has been updated.