BEIJING - United States Defense Secretary Robert Gates on Tuesday added a last-minute Seoul stop to his East Asia itinerary next month, amid wide speculation of US deployment of three nuclear-powered aircraft carriers in East Asia.

"Secretary Gates has added a brief stop in the Republic of Korea (ROK) to his upcoming trip to Asia," Pentagon spokesman Geoff Morrell said in a statement.

Gates and his ROK counterpart will delve into the Democratic People's Republic of Korea's (DPRK) recent actions, and consult on the threats posed by Pyongyang's provocations and its nuclear and missile programs, the statement said.

In another show of strength, the US has dispatched yet another two nuclear-powered aircraft carriers to the western Pacific region - a move widely interpreted as Washington asserting its grip over the escalating situation in East Asia.

According to the official website of the US Navy, the USS Carl Vinson has sealed a three-week composite training unit exercise for a western Pacific deployment.

Another carrier, the USS Ronald Reagan, is also in preparation for an upcoming mission in the same area.

This will infuse new tensions into the region, in addition to the current deployment of the USS George Washington, which earlier took part in Washington's joint military drills with Seoul and Tokyo.

Referring to the deployment, Foreign Ministry spokeswoman Jiang Yu said on Tuesday that China hoped concerned countries should take a responsible attitude to maintain regional stability and promote trust among relevant parties.

The US had wished to downplay the salience of the move, portraying it as "a regularly scheduled 2011 western Pacific deployment". But recent clashes have led some analysts to suspect that there are concerns of a wider conflict.

With the backing of the US, ROK President Lee Myung-bak has been acting tough against the DPRK after his perceived weak response to Pyongyang, said Song Xiaojun, a military expert in Beijing.

"Under mounting domestic pressure, Lee had little choice but to choose harsh retaliation," Song said.

These backlashes have included staging a series of military exercises since the DPRK shelled an island last month, killing four people, and increasing rhetoric - using words such as "merciless counterattack" and "national unity to counter Pyongyang".

But even shadowed in fears of escalating confrontation, both sides have moved to manage the conflict in a more conciliatory manner.

For instance, in the new round of ROK's live-fire drills, the location has veered away from the disputed sea areas.

The DPRK, in return, has touted its "self-restraint" behavior in the face of ROK's ongoing drills.

Song also noted the US deployment of carriers was not necessarily bent on countering Pyongyang, and was far from a smart choice.

"Gates is about to embark on a trip to China, which will be followed by President Hu Jintao's state visit to the US.

Under such circumstances, the deployment of aircraft carriers is diplomatically unwise," Song said.

China Daily