Secretary of State John Kerry said in an interview broadcast on Sunday that he has not ruled out a 2016 White House bid, which would put him in a wide-open Democrat primary field behind front-runner Hillary Clinton.

Kerry, the party’s presidential nominee in 2004, told NBC’s “Meet the Press” that “nobody ever says never.”

However, he said he could think of “no scenario whatsoever” in which he would start such a campaign.

“I haven't thought about it. And I'm, as you can tell, pretty busy," Kerry said from Germany, where he is participating in the Munich Security Conference.

To be sure, as the country’s top diplomat, Kerry has been busy traveling around the world to help resolve an array on international crisis and situations, including the battle against Islamic extremist groups, the Iran nuclear deal, a potential Israel-Palestinian peace agreement and Ukraine’s battle against Russian-backed separatists.  

Among those being mentioned as potential Democratic primary challengers to Clinton, a former secretary of State and 2008 White House candidate, are former Maryland Gov. Martin O’Malley, Massachusetts Sen. Elizabeth Warren and Vice President Joe Biden, who ran for president in 1988 and 2008.

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Clinton has not declared a candidacy.

Kerry, a former Massachusetts senator, has previously suggested that his current job is his last in politics.