WASHINGTON (Yonhap) -- U.S. Secretary of State Hillary Clinton Wednesday met with Chinese Foreign Minister Yang Jiechi as they seek to prepare for Chinese President Hu Jintao's visit to Washington this month on North Korea, the trade imbalance and other issues.   

"We are preparing diligently for the upcoming state visit by President Hu Jintao," Clinton said just before the start of the meeting at the State Department. "Both the minister and I feel a great sense of responsibility to ensure that it continues the positive, cooperative comprehensive relationship between our two countries."

The meeting comes amid a series of conciliatory gestures from North Korea since tensions rose to the highest level since the end of the 1950-53 Korean War last year with the shelling a South Korean front-line island and sinking a South Korean warship.    

Pyongyang earlier in the day called for unconditional dialogue with South Korea.

South Korea instantly rebuffed the proposal as insincere because it came with no apology for the artillery attack on Yeonpyeong Island and the torpedo attack on the Cheonan.

North Korea was high on the agenda Tuesday when Yang met with National Security Adviser Tom Donilon.

"They discussed ways to advance our nonproliferation objectives, including working together to prevent Iran from acquiring nuclear weapons and to persuade North Korea 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. "Mr. Donilon stressed the importance of effective efforts to reduce imbalances in both the global economy as well as in U.S.-China trade."

White House spokesman Robert Gibbs told reporters that North Korea will be high on the agenda at the upcoming summit between Obama and Hu.

"I would say that understand that human rights, the global economy and currency are certainly on the list," Gibbs said. "Of course the situation in North Korea I anticipate will also take up some amount of that time."

State Department spokesman Philip Crowley also said Tuesday that "North Korea will be a topic of discussion" during Clinton's meeting with Yang, who is here to prepare for Hu's state visit to Washington on Jan. 19.

China, host of the six-party talks, has called for their early resumption without preconditions as a way to ease tensions on the Korean Peninsula.

Stephen Bosworth, U.S. special representative for North Korea policy, is currently on a tour of South Korea, China and Japan to discuss ways to revive the nuclear talks, stalled since December 2008 over North Korea's missile and nuclear tests and other provocations.

Upon arriving in Seoul Tuesday, Bosworth said he wants to restart negotiations with North Korea "at a reasonably early date."

He met with South Korean Foreign Minister Kim Sung-hwan and other officials and left for Beijing earlier in the day without meeting with the press.

Crowley Tuesday repeated that North Korea needs to take actions to ease tensions and show its commitment to denuclearization before the six-party talks resume.

North Korea in November revealed a uranium enrichment plant that observers fear could serve as a second way of producing nuclear bombs, aside from plutonium. Pyongyang claims it is producing fuel for power generation.

"We have to be assured that dialogue would be constructive," he said. "We don't just want to have talks for talks' sake."

The flurry of diplomacy comes amid hopes for rapprochement in inter-Korean ties as both Koreas are reaching out to one another to ease tensions.

South Korean President Lee Myung-bak said Monday that the door for inter-Korean dialogue is still open.

Lee also said last week he wants to achieve the North's denuclearization through the six-party talks and inter-Korean dialogue this year, ahead of the North's plans to become a "strong and prosperous state" by 2012, the 100th anniversary of the birth of the North's founder, Kim Il-sung, father of current leader Kim Jong-il.

North Korea has put forth a series of conciliatory gestures through New Mexico Gov. Bill Richardson, who visited Pyongyang last month, including its intentions to reinstate inspectors from the International Atomic Energy Agency at its Yongbyon nuclear facilities.

The monitors' reinstatement is among the preconditions Seoul and Washington have set before the reopening of the multilateral nuclear talks, involving the two Koreas, the U.S., China, Japan and Russia.

North Korea expelled IAEA monitors in early 2009 in the wake of U.N. Security Council sanctions for a missile test. Months later, Pyongyang detonated its second nuclear device, after the first detonation in 2006, drawing harsher U.N. sanctions.