The White House's national security team last fall asked the Pentagon to provide it with options for striking Iran after a group of militants aligned with Tehran fired mortars into an area in Baghdad that is home to the U.S. Embassy, the Wall Street Journal reported Sunday.

The request by the National Security Council, which is led by John Bolton, sparked deep concern among Pentagon and State Department officials, the newspaper reported, citing current and former U.S. officials. (on.wsj.com/2Clg09b)

The Pentagon complied with the request, but it is not known whether the options for an Iran strike were also provided to the White House or if President Donald Trump knew about it.

The decision to seek options striking Iran was prompted by an incident in September in which three mortar rounds were fired into a diplomatic quarter in Baghdad, the newspaper said. The shells landed in an open lot and no one was hurt. Two days later, unidentified militants fired three rockets that hit close to the U.S. Consulate in the southern city of Basra but caused no serious damage.

The State Department and Pentagon did not comment on the report.

NSC spokesman Garrett Marquis, said in a statement on Sunday: "The NSC coordinates policy and provides the president with options to anticipate and respond to a variety of threats" and that it will continue to consider "the full range of options" after the attacks.