SEOUL (Reuters) - A North Korean missile launch may not come for some time although the communist state has been preparing its longest-range rocket for a test flight, South Korea's unification minister said on Wednesday.

North Korea raised regional tensions in recent weeks by threatening to attack the South and preparing its longest-range Taepodong-2 missile for a launch. The missile is designed to carry a weapon as far as Alaska, but has never successfully flown.

I don't believe a missile launch is quite imminent, but there are preparations ongoing, Unification Minister Hyun In-taek told reporters.

The North has said it is preparing to launch a satellite and has the right to do so as part of its peaceful space program. North Korea is barred from test-firing its ballistic missiles under United Nations sanctions.

Stephen Bosworth, the new U.S. special envoy for North Korea, who met Chinese diplomats in Beijing on Wednesday, said their discussions underscored a shared sense that it was important to push forward six-party talks on ending North Korea's atomic ambitions.

Bosworth said China and the United States also shared opposition to a possible North Korea missile launch.

I think there is a great convergence of views about the six-party talks process, Bosworth told reporters after meeting Chinese officials, including Foreign Minister Yang Jieshi.

We are committed to the notion that it's very much important to resume the six-party process as soon as possible... We believe that the six-party process is central to all our efforts to deal with what's happening on the Korean peninsula.

Six-party talks between the two Koreas, China, Japan, Russia and the United States on the North's nuclear weapons programs have stalled, with implementation of an initial energy-for-disarmament deal stuck on Pyongyang's refusal to allow nuclear material to be taken abroad for tests.

North Korea has complained that aid is not being delivered as promised.

Asked about discussions with Chinese side about a possible North Korean missile launch, Bosworth said: We both believe that it would be not a good idea to have a missile launch.

Verification of nuclear facilities is a major obstacle to the success of the talks, China's chief negotiator Wu Dawei told the Xinhua news agency on Wednesday. Xinhua did not report any comments by Wu regarding the missile launch.

PROVOCATIVE MOVES

The United States remains committed to the denuclearization of the Korean peninsula, and the importance of the six-party talks in achieving that goal, Bosworth said.

The U.S. sent Bosworth to Asia this week in a bid to advance the floundering talks and to prevent Pyongyang from making provocative moves.

Beijing is the first stop on the tour to gather views from regional partners as part of the Obama administration's review of North Korea policy.

Bosworth, a former U.S. ambassador to South Korea, will also travel to Tokyo and Seoul, but has no plans at this point to meet North Korean officials on this trip.

No date has been set for a new round of six-party talks.

Analysts have said the North may be looking to launch the missile as soon as next week to mark an election for members of its rubber-stamp parliament. Another possible date is April 25, the anniversary of its Korea People's Army.

Unification Minister Hyun did not say what he based his assessment on, but South Korean officials have said the country receives photographs of sensitive sites in the North from U.S. spy satellites and has its own intelligence on the North.

(Writing by Jon Herskovitz and Lucy Hornby; Editing by Valerie Lee)