U.S. Secretary of State John Kerry cut short a trip to Europe to return home to Boston after breaking his right thigh bone in a bicycling accident Sunday in eastern France.

The accident came as the U.S. — led by Kerry — five other world powers and Iran have resumed efforts to reach a nuclear accord before a June 30 deadline. It is unclear whether the accident will affect those talks. The accord would curb Iran's nuclear program in exchange for an easing of economic sanctions.

The top U.S. diplomat met with his Iranian counterpart, foreign minister Javad Zarif, for about six hours in Geneva on Saturday. The pair's next meeting was expected to be in about two weeks, which would give Kerry some time to start what could be a long recovery.