Air China has postponed Jan. 2's opening of a new route to the North Korean capital, Pyongyang, until March, citing operational reasons, but denied the decision was linked to politics.

Pyongyang failed to meet a Dec. 31 deadline to give a full accounting of its nuclear arms program, considered one of the region's greatest security threats, and answer U.S. suspicions of having a clandestine operation to enrich uranium for weapons.

North Korea has so far kept silent on the issue, as has China, which has hosted numerous rounds of talks between the two Koreas, Japan, Russia and the United States aimed at getting the reclusive state to give up its nuclear ambitions.

Beijing-based Air China would become the only foreign airline to offer scheduled services to North Korea, whose air links are almost entirely provided by the Russian-built aircraft of state carrier Air Koryo.

"It's been pushed back until March as related preparatory work is still going on," said Air China spokesman Wang Yongsheng, without elaborating. "On Air China's side, preparations are basically complete."

"There are no political reasons," he added.

Wang said Air China still saw much potential in the route, which would make Pyongyang a Star Alliance destination, the airline grouping led by Singapore Airlines, Lufthansa and United Airlines which Air China recently joined.

"Flying to Pyongyang is basically a tourist route. The main customers will be Chinese. Very few North Koreans come to China on holiday," he said. "We have a lot of confidence the route will make money."

Isolated North Korea permits only a tiny number of foreign visitors a year who must travel with an approved travel agency on tightly controlled tours.

But Chinese can visit with relative ease, and many ethnic Koreans who live across the border in China go regularly on business trips.

Previously, China Southern Airlines has flown to Pyongyang. It stopped flights in 2006 soon after North Korea carried out a nuclear test, though it was not clear if Beijing ordered the airline to drop the route.