Story highlights Vice President Joe Biden told a crowd of Israel supporters that terrorism can never be justified

But he chided Israel's government for settlement expansion

(CNN) Vice President Joe Biden Sunday defended last year's Iran nuclear deal in a speech to more than 18,000 pro-Israel activists, comments that did not seem to be met with much support from the audience. Many leaders in the American Jewish community had voiced opposition to the agreement reached between the U.S., its allies and Iran to curb Tehran's nuclear program because they did not trust Iranian leaders, who have vowed to attack Israel.

Speaking to the annual American Israeli Public Affairs Committee (AIPAC) convention, Biden touted how much of Iran's stockpile of low-enriched uranium has been shipped out of the country and many of its centrifuges have been removed, saying that nation is much further away from obtaining a nuclear weapon than a year ago.

But he assured the audience, many of whom are skeptical about Iran's intentions, that the U.S. is not taking Tehran solely at its word that it will continue to comply with the deal.

"We are watching Iran like a hawk," Biden said. "If Iran violates the deal the U.S. will act. The U.S. will act. Our commitment is unambiguous."

The Vice President pointed out other sanctions against Iran -- for its support of terrorism and its ballistic missile program -- are still in place.

Read More