NEW YORK (CBSNewYork/AP) — U.S. Sen. Charles Schumer is not ready to back the Obama administration’s nuclear deal with Iran.

Schumer, the third highest ranking Democrat in the Senate, said Monday he is pouring over the deal before making a decision on how he’ll vote.

“I’ve read the agreement a bunch of times, but there are lots of other questions that relate to the agreement that are not in it,” he told reporters, including WCBS 880’s Rich Lamb. “I’ve had over 20 briefings, two classified briefings. I intend to continue that.

“The White House is making every effort to answer my questions, so are the people who are opposed. There are many different views and many different questions. The questions relate to what will happen if there is an agreement, if this agreement goes into effect (and) what will happen if it doesn’t.”

The Republican-led Congress is in the midst of a 60-day review of the deal, and is expected to vote in September on a resolution of disapproval that Obama has vowed to veto.

Schumer, meanwhile, is being pulled in two directions. While he is staunchly pro-Israel and has a large Jewish constituency, he’s also in line to become the leader of the Democratic caucus in 2016 and the White House wants him to rally the votes to prevent a veto override.

“This is such an important decision that I will not let pressure, politics or party influence,” Schumer said.

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