The United States agreed to a request by South Korea to delay the transfer of wartime operational control of troops on the Korean Peninsula.

The decision to postpone the control of forces from 2012 to 2015 followed a meeting between U.S. President Barack Obama and South Korean President Lee Myung-bak in Toronto.

U.S. Defense Department officials were quoted as telling U.S. media that by extending the deadline, the transfer would proceed more smoothly and allow the U.S. and South Korean forces to be more in sync.

"We have arrived at an agreement that the transition of operational control for alliance activities in the Korean peninsula will take place in 2015," Obama said after his talks with Lee. "This gives us appropriate time … within the existing security context, to do this right, because this alliance is the linchpin of not only security for the Republic of Korea and the United States but also for the Pacific as a whole."

Obama said his country would continue to do whatever was required to fend off aggression from North Korea. It remained unclear whether the delay was prompted after the sinking of the South Korean warship Cheonan, which killed 46 sailors.

During a news conference at the Group of 20 meetings in Toronto last weekend, Obama praised Lee's restraint in the wake of March sinking which an international investigation said was prompted by a North Korean torpedo.

An estimated 28,500 U.S. troops are based in South Korea to deter potential aggression from North Korea.

Although the Korean War ended in 1953, the countries haven't signed a peace agreement, remaining divided by one of the world's most fortified borders.

The Korea Herald suggested that a premature transfer of operational control could imperil stability in a volatile region.

It reported that some 9.8 million people have participated in a signature-collecting campaign supporting the transfer delay.

Specific details of how the wartime control will shift will be discussed in a relevant meeting by South Korea and the United States officials next month.

Still, The Korea Herald reported that both sides had "tentatively agreed to relocate the U.S. base in Yongsan to Pyeongtaek by 2015 and the U.S. 2nd Infantry Division by the first half of 2016."

It said both sides had been considering a delay in the wartime control transfer even before the March attack on the Cheonan.

South Korea was working with the United Nations to produce a strongly worded condemnation of North Korea.

"It is absolutely critical that the international community rally behind (South Korea) and send a clear message to North Korea that this kind of behavior is unacceptable," Obama said, "and that the international community will continue to step up pressure until it makes a decision to follow a path that is consistent with international norms."