Sen. John Kerry (D-Mass.) blasted former Massachusetts Gov. Mitt Romney (R) on Wednesday for politicizing the debate over a nuclear arms treaty in the Senate. 

Kerry, the chairman of the Senate Foreign Relations Committee, took his Massachusetts colleague to task over an op-ed Romney wrote in the Washington Post on Tuesday urging the Senate to reject the New Strategic Arms Reduction Treaty (New-START).

“I have nothing against Massachusetts politicians running for president,” Kerry wrote in the Washington Post on Wednesday in response. “But the world’s most important elected office carries responsibilities, including the duty to check your facts even if you’re in a footrace to the right against Sarah Palin.”

Kerry sought to refute Romney’s objections to the treaty, saying the pact with Russia would not constrain the ability of the United States to defend itself, while putting into place aggressive checks against Russia’s nuclear arsenal. Kerry also touted bipartisan support from lawmakers and diplomats for the agreement.

President Barack Obama signed the treaty with Russian President Dmitry Medvedev earlier this year, and has said he’d like to see it ratified by this November’s elections. To that end, the treaty has advanced steadily through the foreign relations panel with a series of hearings in recent weeks. 

But in addition to defending New-START on its merits, Kerry ridiculed Romney, a 2008 GOP presidential candidate and potential 2012 candidate, for a lack of seriousness when it comes to national security. 

“Responsible political figures across the spectrum need to support every step possible to control the spread of nuclear weapons,” wrote Kerry, himself the 2004 Democratic presidential nominee. “Rather than pander to politics, we need to ratify this agreement quickly. Every day without its verification regime is a day without a clear view of Russia’s nuclear arsenal.”

“More than that, you need to understand that when it comes to nuclear danger, the nation’s security is more important than scoring cheap political points,” Kerry wrote elsewhere in the piece.