A U.S. aircraft carrier has been dispatched to waters off Yemen to join other American ships prepared to block any Iranian shipments to the Houthi rebels fighting in Yemen.

The U.S. Navy has been beefing up its presence in the Gulf of Aden and the southern Arabian Sea amid reports that a convoy of about eight Iranian ships is heading toward Yemen and possibly carrying arms for the Houthis.

A Navy official confirmed to Fox News that the USS Theodore Roosevelt — along with her escort ship, the USS Normandy, a guided-missile cruiser — left the Persian Gulf on Sunday en route for the Arabian Sea, to help enforce the blockade.

Tensions are rising in the region even as the U.S. and five other world powers scramble to strike a final deal with Iran on its nuclear program by the end of June. The fighting in Yemen, where U.S. ally Saudi Arabia is leading a coalition against the Iran-backed rebels, is complicating matters.

White House Press Secretary Josh Earnest, without commenting specifically on any Navy movements, said the U.S. has concerns about Iran’s “continued support” for the Houthis.

“We have seen evidence that the Iranians are supplying weapons and other armed support to the Houthis in Yemen. That support will only contribute to greater violence in that country,” he said. “These are exactly the kind of destabilizing activities that we have in mind when we raise concerns about Iran’s destabilizing activities in the Middle East.”

He said “the Iranians are acutely aware of our concerns for their continued support of the Houthis by sending them large shipments of weapons.”

A written statement from the Navy on Monday said the two ships are joining others in conducting “maritime security operations” in the region.

“In recent days, the U.S. Navy has increased its presence in this area as a result of the current instability in Yemen,” the statement said.

“The purpose of these operations is to ensure the vital shipping lanes in the region remain open and safe. The United States remains committed to its regional partners and to maintaining security in the maritime environment.”

The Houthis are battling government-backed fighters in an effort to take control of the country.

There are now about nine U.S. Navy ships in the region, including cruisers and destroyers carrying teams that can board and search other vessels, as well as three support ships.

The U.S. Navy generally conducts consensual boardings of ships when needed, including to combat piracy around Africa and the region. So far, however, U.S. naval personnel have not boarded any Iranian vessels since the Yemen conflict began.

SOURCES
Fox News’ Lucas Tomlinson and The Associated Press contributed to this report.