Massachusetts US.. Senator Ed Markey says he still hasn’t decided how he will vote on the nuclear deal with Iran.

During a visit to Springfield Tuesday, Markey said there is one area he continues to focus on as he ponders how to vote on the agreement.

“The key is to make sure that there is a verifiable inspections regime, which is in place in order to determine the efficacy of the deal long term,” Markey says.

If Congress votes on a resolution not accepting the Iran accord, the President can still get the deal through if he can find enough lawmakers to uphold his likely veto.

Markey’s Senate colleague, Elizabeth Warren, and Congressman Jim McGovern have already announced their support of the deal while Congressman Richard Neal has not said publicly which way he will vote.