Pentagon spokesman Steve Warren dismissed on Monday reports that the ships the US has sent to the waters near Yemen were on a mission to intercept alleged Iranian arms shipments to Yemen.
The United States sent the carrier USS Theodore Roosevelt and its escort cruiser, USS Normandy, from the Persian Gulf into the Arabian Sea on Sunday to join seven other US warships, including two destroyers, two mine-sweepers and three amphibious ships carrying 2,200 US Marines, in the waters near Yemen, Reuters reported on Monday.
The US Navy said it had increased its presence in the area because of instability there. It said in a statement that the purpose was to "ensure the vital shipping lanes in the region remain open and safe."
The move has come as US officials say they are closely monitoring an approaching convoy of Iranian ships they claim is heading toward Yemen with unknown cargo aboard.
The US has been supplying arms to a Saudi-led coalition which has been carrying out aerial attacks against Houthi fighters, which have taken control of the Yemeni capital Sanaa and vast areas in the impoverished Arab country.
Houthis' offensive on the south, backed by army units, prompted Saudi Arabia to launch its air campaign on March 26 alongside regional Arab allies.
