Iran warned the United States on Monday that energy infrastructure across the Gulf, including U.S. oil and gas interests, is vulnerable, and threatened retaliation for any new U.S. attacks. Iranian Parliament Speaker Mohammad Baqer Qalibaf was quoted as saying, "Strike our assets and you get struck."

The warning followed U.S. and Iranian strikes on shipping over the weekend, which pushed oil prices to near six-week highs on Monday. The latest exchange shows no sign of progress toward a diplomatic breakthrough that could end more than six months of conflict and restore normal energy flows through the Gulf.

Iran has tightened restrictions on shipping through the Strait of Hormuz, a critical artery for global oil shipments.