BEIJING: China is committed to plans to expand a Pakistan nuclear power plant using 1970s technology, experts say, even after Japan's crisis triggered global alarm about atomic safety.

China's construction of reactors at the Chashma nuclear power plant in the Punjab region of Pakistan drew international unease well before the March 11 earthquake and tsunami battered the 1970s vintage nuclear reactors in Japan, crippling cooling systems and causing radiation to leak into the surroundings.

Those worries could now multiply. But neither Beijing nor Islamabad is likely to cut short their nuclear embrace.

China's nuclear ties with long-standing partner Pakistan have triggered unease in Washington, Delhi and other capitals worried about Pakistan's history of spreading nuclear weapons technology, its domestic instability, and the potential holes created in international non-proliferation rules.

Safety is also a major concern, as the reactors at Chashma, including the third and fourth units China has planned, are derived from designs dating back to the 1970s, said Mark Hibbs, an expert on atomic policy at the Carnegie Endowment for International Peace, who has closely followed Chinese-Pakistani nuclear cooperation.

This means they have fewer safety features than the newer models Beijing will increasingly use for domestic nuclear plants.

“The oldest reactor (design) that China is building is this reactor in Pakistan. It's a very old design,” said Hibbs, who is based in Berlin and visited Pakistan this week.

“If China wants to help Pakistan build a reactor right now, they're locked into this design,” Hibbs said in a telephone interview, citing patent restrictions and atomic export barriers that prevent China from selling more up-to-date designs abroad.

The radiation leaks at Japan's Fukushima nuclear plant are likely to raise new questions about whether China should pursue nuclear power expansion in Pakistan, and whether it must first seek approval for planned reactors from other nuclear exporting states.

Beijing remained committed to Chashma, and would probably not seek a green light from a nuclear trade group, said Li Hong, a prominent Chinese nuclear expert.

“There's no doubt that China will go ahead with Chashma, because this cooperation with Pakistan has such a long history,” said Li, Secretary General of the China Arms Control and Disarmament Association, a government-sponsored think tank in Beijing that focuses on nuclear proliferation issues.

“China will absorb lessons about nuclear safety from Japan's problems, including for Chashma,” said Li.

A nuclear showcase

The Chashma power plant is one of two using nuclear reactors in Pakistan. Two of its reactors are already producing electricity in a country with chronic power shortages and China is helping build two more reactors.

The plant is located on plains near the banks of the Indus River, hundreds of miles to the south of Kashmir, the site of a 7.6 magnitude earthquake in 2005 that officials say killed 75,000 people. It was also not damaged in last year's devastating floods.

China suspended approvals last week for new domestic nuclear plants. But reports on Chinese nuclear websites show work on Chashma continued after the calamity hit Japan.

On March 14, two days after Japan's earthquake, Chinese engineers helped run the first successful test for linking the new Chashma reactor unit to a power grid, according to Shanghai Nuclear Engineering Research and Design (www.snerdi.com.cn), which is helping build it.

Last month, the China National Nuclear Corp, the nation's dominant atomic company, held a two-day meeting to refine plans for work at Chashma in 2011, when the new, second reactor is due to go into service (www.cnnc.com.cn).

“In 2011, we will strive to bring the project into commercial operation two months ahead of schedule,” said the report from that meeting.

China's nuclear industry sees Chashma as a showcase of the country's ability to export reactors, a trade that Beijing hopes will grow.

“Currently, we're still a blank in exporting large-scale, multi-megawatt nuclear power stations, apart from the Chashma 300-megawatt water pressurised nuclear power station,” Zhao Zhixiang, director of the science and technology committee of the Chinese Institute of Atomic Energy, told China Energy News, a Chinese-language paper, earlier this month.

“The key to becoming a nuclear energy power is to establish your own abilities and competitiveness,” he said.

“No cause for concern”

Rivals India and Pakistan both possess nuclear arsenals and both refuse to join the Nuclear Non-Proliferation Treaty (NPT), which would oblige them to scrap those weapons.

The International Atomic Energy Agency, the United Nations' nuclear watchdog agency, agreed in early March to Pakistan's request to safeguard the two new reactors planned for Chashma, a step that would allow the agency to help ensure nuclear material from the reactors is secure and not diverted into weapons-related programmes.

"There is no cause for concern regarding the safe operation of these plants," a spokesman for the Pakistan Atomic Energy Commission (PAEC) said of Chashma. "Any lessons learnt from the accidents in Japan will be implemented at our plants as well."

Washington and other governments have said China should seek approval for the planned reactors from the Nuclear Suppliers Group (NSG), a consensus-based cartel that seeks to ensure nuclear exports do not get used for non-peaceful purposes.

When the United States sealed its own controversial nuclear energy agreement with India in 2008, it won a waiver from that rule from the NSG after contentious negotiations in which China raised misgivings.

Beijing is likely to shun calls to seek special approval, arguing the two new units planned at Chashma come under a bilateral agreement sealed before it joined the NSG in 2004.

"I don't think that China will seek approval from the NSG," said Li, the arms control association official. "China considers that the new reactors were grandfathered under a previous agreement," he said.

Other NSG members, including the Washington and other Western governments, are likely to want assurance that the two reactors planned for Chashma will be the last that China claims need no approval, said Hibbs.

Last year, the China National Nuclear Corp said it was in talks to build a separate 1-gigawatt atomic plant in Pakistan.