McCain tweeted "Thanks Vlad" on Thursday.

McCain has a long history of tweaking Putin through Twitter, and Putin has not always taken it well.

Last year, McCain suggested in a tweet that Putin would soon have his own “Arab Spring” rebellion to deal with, and then-Prime Minister Putin retaliated by suggesting McCain had gone “nuts” during his time as a prisoner of war.

“I think that obviously Mr. Putin, ‘Vlad’ as I love to call him, is a little bit stunned," McCain joked in response.

McCain might find it easier to rely on the National Aeronautics and Space Administration's (NASA) evaluation of the rumors that the Mayan culture predicted the world will end on Dec. 21. 

NASA has released a video reassuring people that the world will not end on Friday, and posted on their website's Frequently Asked Questions section:

The world will not end in 2012. Our planet has been getting along just fine for more than 4 billion years, and credible scientists worldwide know of no threat associated with 2012.

The agency has received thousands of letters concerned about the doomsday theory, and this week is using their official Twitter account to reassure people "nothing bad will happen to the Earth this Friday."