Canada may be the subject of some controversy at the nuclear security summit, which opens today in Seoul, South Korea.
The U.S. and several European countries are calling on countries such as Canada to phase out the use of highly enriched uranium, which Canada uses to make medical isotopes for medical diagnoses. Canada is the largest producer of medical isotopes.
"Highly enriched uranium can be used to make bombs, and the U.S. is calling on Canada and others to move toward using a lower grade," the CBC's Laurie Graham reports from the conference.
For Canada, "the cost of converting to get into a lower grade would be very expensive. Canada had promised in 2010 to start phasing out using it at the last summit. It's been sharply criticized for not moving fast enough, and no doubt that criticism will continue."
Prime Minister Stephen Harper shakes hands with Korean President Lee Myung-bak as he arrives at the Nuclear Security Summit in Seoul on Monday. Prime Minister Stephen Harper shakes hands with Korean President Lee Myung-bak as he arrives at the Nuclear Security Summit in Seoul on Monday. 

Prime Minister Stephen Harper arrived in Seoul for the conference earlier. He made his way there via Japan, where the government announced today it has shut down another nuclear plant, as concern over last year's tsunami and meltdown in northern Japan continues. Out of 54 nuclear power plants, only one is still operating, and it is set to go offline in May.
The security summit was supposed to be an opportunity for U.S. President Barack Obama and leaders from 50 other countries to find ways to keep nuclear material away from terrorists. So far, however, North Korea has upstaged that agenda, which may be what Pyongyang intended, The Associated Press said.
Several of the heads of state gathered for the two-day summit have criticized the North's surprise announcement 10 days ago that it plans to blast a satellite into space next month aboard a long-range rocket — a launch that Obama's government views as cover for nuclear missile development.
Obama urged North Korean leaders to abandon their rocket plan or risk jeopardizing their country's future and thwarting a recent U.S. pledge of food aid in return for nuclear and missile test moratoriums — considered a breakthrough after years of deadlock. South Korean President Lee Myung-bak's government warned it might shoot down parts of the rocket if it violates South Korean air space.
Obama and Lee have pressed North Korean ally China to use its influence to prevent a launch.
'I think North Korea did this to overshadow our talks about nuclear security.'
A Chinese government-backed disarmament expert said allowing the launch to dominate discussions at the summit may be exactly what North Korea wants.
"I think North Korea did this to overshadow our talks about nuclear security," said China Arms Control and Disarmament Association head Li Hong. "We shouldn't fall for their trick."
North Korea has a history of attention-grabbing moves linked to its nuclear and ballistic missile programs that analysts say are meant to maximize the impoverished nation's leverage in talks aimed at trading disarmament pledges for much-needed aid.
Still, why North Korea made its announcement so soon after settling the nuclear freeze-for-aid deal with the United States has perplexed many observers.

Better the crisis, better the deal

The North has previously sparked hopes for a diplomatic solution to a standoff over its nuclear program, before creating a crisis to put itself high on world agendas and then offering to come back to talks, expecting to extract more aid than originally promised, said Ralph Cossa, president of Pacific Forum CSIS, a Hawaii-based think-tank .
"If they raise hopes, then dash hopes, then come back again, they think they might get a better deal," Cossa said. "The better the crisis, the better the deal."
The drama over the North Korean satellite launch has robbed attention from the summit's moves to lock down the world's supply of nuclear material by 2014. Participants were to sign a communiqué on those efforts Tuesday.
It also takes the spotlight away from diplomacy meant to halt Iran's suspected nuclear weapons program, though Obama stressed that he would press the issue of Iran in one-on-one talks with the leaders of Russia and China.
"Iran's leaders must understand that there is no escaping the choice before it," Obama said. "Iran must act with the seriousness and sense of urgency that this moment demands. Iran must meet its obligations."

Help achieve its interests

North Korea has said it would launch its rocket around the April 15 celebration of the birthday of North Korean founder Kim Il Sung, and this timing is probably not linked to this week's nuclear summit, said Koh Yu-hwan, a North Korea professor at Seoul's Dongguk University. However, the North may have timed its March 16 launch announcement with the global meeting in mind, he said.
U.S. President Barack Obama urges North Korea to give up its nuclear ambitions during a speech at Hankuk University in Seoul, South Korea, on Monday. U.S. President Barack Obama urges North Korea to give up its nuclear ambitions during a speech at Hankuk University in Seoul, South Korea, on Monday."North Korea can demonstrate to the world how volatile and tense the situation on the Korean peninsula is" with the launch, he said. "That would help it achieve its interests in future negotiations."
North Korea also moved its rocket into position just before the summit opened, South Korean officials said Sunday.
North Korea has determined it can still win U.S. food aid even if it fires a long-range rocket, said Baek Seung-joo, an analyst with the state-run Korea Institute for Defence Analyses in South Korea. It could conduct a third nuclear test if the U.S. doesn't send its promised food aid, Baek said.
Yoo Ho-yeol, a professor at Korea University in the South, said Pyongyang has decided to launch a satellite because it believes it will help solidify new leader Kim Jong-un's power at a time when it has vowed to build a thriving nation.
"North Korea hasn't many things to show off," he said.

China under pressure

China, as North Korea's biggest source of diplomatic support and economic assistance, faces pressure to get the North to halt its rocket plans. However, China maintains its leverage is limited by Pyongyang's unpredictable nature and Beijing's overriding concern for stability along its northeastern border.
Chinese President Hu Jintao, in a meeting Monday morning with the South Korean president, expressed his country's concerns about the launch plans and said Beijing would continue to urge North Korea to cancel them, South Korean presidential official Kim Tae-hyo told reporters.
China will continue to express its concerns to North Korea — and may send a high-level official to Pyongyang to press its case — but won't cut off aid for fear of destabilizing the new government, Peking University international relations expert Zhu Feng.
This would be the fourth North Korean launch of a long-range multistage rocket since 1998. The UN Security Council condemned North Korea's last long-range rocket launch in 2009. Pyongyang responded by abandoning six-nation nuclear disarmament talks and, weeks later, carrying out a nuclear test, its second.