A third round of six-nation talks on North Korea's nuclear weapons programme opens this week with Washington in the hot seat, as pressure builds for it to change tack from its hardline stance. With presidential elections looming in November, the administration of US President George W. Bush has managed to keep the North Korean issue on the back-burner - and that is the way it wants it to stay, analysts say. The problem is that the other nations are getting restless. Cracks could appear in the talks, which start in Beijing on Wednesday and scheduled to run until Saturday. 'If North Korea rises to a level of importance, Bush could be in a position where he has to concede, but there is no evidence the administration is ready to concede,' said Paul Harris, an expert on US foreign policy at Lingnan University in Hong Kong. 'If North Korea already has nuclear weapons and is exporting this kind of technology, then this becomes a bigger threat, a bigger threat' than ex-Iraqi dictator Saddam Hussein. 'If this idea gains traction and becomes bigger news, then the US will have to respond. So they want to keep it at a low level.' Two previous rounds of six-way talks hosted by China and also involving Japan, Russia and South Korea, have failed to narrow key differences on how to end the 20-month-old standoff. Washington is demanding the complete, verifiable and irreversible dismantling of both the plutonium and enriched uranium programmes. Pyongyang denies it is running a uranium project, but has offered to freeze its plutonium facilities in return for simultaneous rewards from the US. US Secretary of State Colin Powell stressed as recently as last month that all the five parties talking to North Korea were united in their stand for it to disband its nuclear programme completely, but others disagree. Zhao Huji, a North Korea specialist at the Central Party School in Beijing, said fissures were appearing. 'At the beginning, all five countries tried to persuade North Korea [to make concessions]. Now, the very hard line of the US is not supported so much by the others,' he said. 'The countries close to the Korean peninsula are pushing so that things advance. Only the US does not want this to happen.'