A senior U.S. envoy said Wednesday that Seoul and Washington were closely coordinating their policies over North Korea amid tension following the North's deadly artillery attack on a front-line South Korean island.

Stephen Bosworth held separate talks with the foreign minister and with Seoul's top envoy on North Korean nuclear matters. Details of the two meetings were not immediately available.

A North Korean Nov. 23 artillery barrage on Yeonpyeong Island killed two South Korean marines and two civilians, fueling fears of a war on the divided peninsula.

South Korea has vowed to retaliate against North Korea if provoked again, but has recently opened the door to possible peace talks with the North.

Asked whether Washington had put any pressure on Seoul, Bosworth said "never" as he left the foreign ministry. He didn't elaborate.

The U.S. envoy arrived in Seoul on Tuesday as part of a tour that also includes stops in China and Japan. Bosworth expressed hopes Tuesday that serious negotiations on North Korea will start soon.

He didn't elaborate and it wasn't clear if he was referring to stalled six-nation nuclear disarmament talks or something else.

He said he will continue to coordinate closely with China, the North's major ally.

In Washington, China's foreign minister discussed North Korea's nuclear program with U.S. national security adviser Tom Donilon in a White House meeting on Tuesday.

They discussed ways to persuade Pyongyang to abandon its nuclear weapons program, to meet its commitments and international obligations and to avoid destabilizing behavior, the White House said in a statement.