AP:

In an unexpected reversal, President Barack Obama declined to sign a renewal of sanctions against Iran but let it become law anyway, in an apparent bid to alleviate Tehran's concerns that the U.S. is backsliding on the nuclear deal.

Although the White House had said that Obama was expected to sign the 10-year-renewal, the midnight deadline came and went Thursday with no approval from the president. White House press secretary Josh Earnest said Obama had decided to let it become law without his signature.

Iran had vowed to respond if the sanctions were renewed, arguing they violate the nuclear deal between Iran and world powers, which eased sanctions in exchange for curbs on Iran's nuclear program. Iran's government has complained to the United Nations about the renewal, and on Tuesday, Iran's president ordered up plans to build nuclear-powered ships and to formally accuse the U.S. of violating the terms of the deal.

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