The Pentagon is denying reports from Seoul there will be a joint U.S.-South Korean naval exercise as early as next week in response to the conclusion of an international investigation that North Korea sank a South Korean ship in March. Officials also deny that there is a plan for a U.S. aircraft carrier to be involved in any exercises off the Korean coast.

Two senior spokesmen have denied the reports. In an e-mail, Pentagon Press Secretary Geoff Morrell said "no carriers are going anywhere near the Korean peninsula anytime soon." Morrell is in Singapore, where U.S. Defense Secretary Robert Gates will discuss the Korean tensions with his South Korean and Japanese counterparts, as well as with senior defense officials from other Asian nations. Morrell says Gates has made no decision to send an aircraft carrier to the region, and no such decision is expected soon.

In Seoul, the defense ministry spokesman told reporters earlier that a U.S.-South Korean naval exercises will start on Monday in the Yellow Sea, near the area where the South Korean ship was sunk. Some reports said it would involve a U.S. aircraft carrier based in Japan.

But at the Pentagon, spokesman Bryan Whitman said that is not accurate.

"There have not been any decisions with respect to these reports I see about carrier exercises," said Bryan Whitman. "I have talked to you about the exercises that the United States is contemplating and planning with respect to the Republic of Korea. And those are some maritime security exercises and an anti-submarine exercise that is going to take place later this month or early next month."

Whitman had previously announced those two joint U.S.-South Korean naval exercises in response to the ship sinking. Another official says there could be a joint U.S.-South Korean announcement in Seoul on Friday to clarify exactly what exercises will be held, and when, and which ships will be involved.

Some experts caution that if an aircraft carrier is sent it could provoke a strong reaction from North Korea. American aircraft carriers are the largest and most capable navy ships in the world, with dozens of fighter jets and other significant firepower on board.

Shortly before landing in Singapore Thursday evening, Secretary Gates told reporters on his plane the United States is considering additional joint exercises with South Korea, but he did not provide specifics.

"An important element this time will be to reassure the South Koreans of our support as they face these provocations and a North [Korea] that seems even more unpredictable than usual," said Robert Gates.

The international investigation concluded that a torpedo fired by a North Korean submarine sank the South Korean Navy ship the Cheonan, killing 46 men on board. North Korea has denied involvement.

Gates had hoped to discuss the Korean tensions with Chinese officials during his trip, but China said 'no' to his plan to visit Beijing and did not even send a senior delegation to the annual Singapore conference.