The U.S. Justice Department is reportedly considering a lawsuit to block Korean Air's planned acquisition of Asiana Airlines.

Citing three people familiar with the deliberations, U.S. news website Politico reported on Thursday that the department is considering the suit out of concern that the deal might harm competition on passenger and cargo traffic between South Korea and the U.S.

The outlet said, however, that no decision has been made on whether to bring a case, and nothing is imminent, with the sources adding that the department could ultimately not take any action.

Politico said that although the U.S. does not have jurisdiction over airlines based in South Korea, it can still seek to block the merger on the basis of harm to competition in the U.S.