A NL East team is at the head of the Roy Oswalt rumor mill, but it’s not the Mets.

MLB.com reports the Nationals have expressed interest in acquiring the Astros righty, who requested a trade from the team. But the Nationals would have to be willing to pay Oswalt’s hefty contract, which pays him $31 million over the rest of this season and 2011. And even though Oswalt, 32, requested a move out of Houston, he does have a no-trade clause and could veto a move to the nation’s capital if he didn’t like the situation.

KERNAN: METS NEED OSWALT

“We have interest in a lot of people,” Nationals GM Mike Rizzo told the Washington Post. “We’re always on the phones, we’re always doing our due diligence on players. Oswalt is a tremendous competitor and a tremendous pitcher.”