MOSCOW (Yonhap News) ― Top North Korean officials have vowed to move ahead with an ambitious project to build a pipeline through their isolated country to ship Siberian gas to South Korea.

The North Korean officials reaffirmed their commitment to Russia following the death last month of their former leader Kim Jong-il, according to a diplomatic source in Moscow, without identifying the North Korean officials.

Russia’s Energy Minister Sergei Shmatko conveyed the North’s intention to the South Korean ambassador to Moscow, Wi Sung-lac, on Wednesday, the source said.

Shmatko said a key issue is to revitalize consultations on the price of natural gas, according to the source.

Calls to the Russia’s Energy Ministry seeking comment went unanswered early Friday.

The project, first envisioned about 20 years ago, has gained momentum since August when then North Korean leader Kim Jong-il expressed his willingness to permit a pipeline to go through his country during summit talks with Russian President Dmitry Medvedev.

In November, South Korean President Lee Myung-bak also agreed with Medvedev to work closely on the project, saying it would benefit all three countries involved.

In September, Russia’s state-run gas firm Gazprom signed a memorandum of understanding with its South Korean counterpart to start construction of the pipeline in 2013 and to ship gas through the connection from 2017.

South Korean officials have downplayed the significance of that timeline, noting the project still has a long way to go. Russia and North Korea have yet to agree on pipeline transit fees.

Officials and experts have said the project could help reduce inter-Korean tensions that peaked in the wake of Pyongyang’s two deadly attacks on the South in 2010.