Kaine is staying mum on reports he is on the top of Obama's VP list.

(CNN) - The vice presidential buzz is circling around Gov. Tim Kaine, but the Virginia Democrat refused to address the speculation in a radio interview Tuesday.

"What I said about this is that I have been on board with the campaign since February 2007, but I don't talk about my conversations with the campaign," the first-term governor told Washington radio station WTOP. "You know I save my advice, thoughts, etc., for those conversations and I don't really share them."

Kaine, who hails from an increasingly purple state the Obama campaign hopes to snatch from Republicans this cycle, has long been considered a top vice presidential prospect. But speculation increased Monday night after both the Washington Post and the Politico reported Kaine is on top of the Illinois senator's VP short list.

According to the Washington Post, Kaine has told his close advisers he has had "very serious" conversations with the Obama campaign about the position and is eagerly jockeying for it.

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But speaking to WTOP on Tuesday, Kaine said he did not endorse Obama to "get anything or get appointed to anything."

"It's flattering to be mentioned, my mom loves it, she calls me, she sees it," he said. "But that's for the campaign to decide. The campaign has made very good decisions thus far. And I think, how ever they decide, they are going to make a very good decision about Senator Obama's running mate."

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Later in the broadcast, Kaine also refused to say whether he has any meetings planned with Obama: "I've got my 13-year old daughter in the studio. We have a date right after this and that's the only thing on my calendar."

Many political observers have noted Kaine would bring several advantages to the Democratic ticket - in addition to hailing from a conservative-to-moderate state, he has never served in Washington and could easily espouse Obama's message of change. He, like Obama, is also a fresh face in political circles and a graduate of Harvard Law School.

But Kaine has only served as governor for three years, and it's likely his name on the ticket will do little to assuage voter concerns that Obama lacks the experience to be president. Kaine also does little to shore up the Illinois senator's short resume on national security credentials.