The United States has dispatched the aircraft carrier USS Theodore Roosevelt toward the waters off Yemen to join other American ships preparing to intercept any Iranian vessels carrying weapons to the rebels, U.S. officials said.

The US said it sent the USS Theodore Roosevelt, escorted by guided-missile cruiser USS Normandy, "to ensure the vital shipping lanes in the region remain open and safe", bringing the number of American ships in the area to nine.

The announcement that the USS Theodore Roosevelt was heading for the region came amid reports that a convoy of Iranian ships may be headed toward Yemen to arm the Houthis.

The Iranian convoy is comprised of nine ships, including two patrol boats, a senior defense official told AFP, saying its exact destination was unknown.

Pentagon spokesman Colonel Steven Warren denied reports the US ships have orders to intercept Iranian vessels carrying weapons for the Houthis.

White House spokesman Josh Earnest, on the other hand, would not comment specifically on any Navy movements in Yemeni waters, but 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," White House spokesman Josh Earnest said. "That support will only contribute to greater violence in that country. 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."

The United States says it is not taking part directly in the strikes, but is providing intelligence and logistical support.

Yemen, strategically located near key shipping routes and bordering oil-rich Saudi Arabia, was plunged into chaos last year when the Iran-backed Houthi Shiite rebels seized the capital Sanaa.