North Korea and the United States have both made conciliatory remarks as fresh six-nation talks on North Korea's nuclear programme opened in Beijing.
There were smiles despite the gulf between the sides
North Korean negotiator Kim Kye-gwan said Pyongyang was ready to work to free the peninsula of nuclear weapons.
The US said it viewed North Korea as a sovereign state which it had no intention of attacking.
Pyongyang wants a peace treaty with the US, plus aid in exchange for scrapping its nuclear programme.
The talks mark the end of a 13-month boycott by North Korea.
But Mr Kim said the beginning of the talks was only a first step.
"Opening talks is important, but what is more important is to achieve actual progress such as denuclearisation," Mr Kim said.
He said the North and "other parties including the United States" were ready for such a move.
South Korea urged a quick resolution of the long-running stand-off between Washington and Pyongyang.
"Time is not on anyone's side," South Korean Deputy Foreign Minister Song Min-soon said.
Oct 2002: US says North Korea is enriching uranium in violation of agreements
Dec 2002: North Korea removes UN seals from Yongbyon nuclear reactor, expels inspectors
Feb 2003: IAEA refers North Korea to UN Security Council
Aug 2003:First round of six-nation talks begins in Beijing
Feb 2005: Pyongyang says it has built nuclear weapons for self-defence
Unusually, no end date has been set for this round of talks between North and South Korea, the US, China, Russia and Japan.
US envoy Christopher Hill said the Americans would stay at the talks "so long as we are making progress".
He said nuclear weapons would not make North Korea more secure.
"And in fact, on the contrary, nuclear weapons on the Korean Peninsula will only increase tension in the region," he said.
The six-party talks had been stalled for more than an year after North Korea withdrew, blaming US aggression.
South Korea began to deliver food aid to the North as the talks began, part of an earlier pledge to send 500,000 tons of rice to its impoverished neighbour.
South Korea began aid deliveries as the talks opened
The BBC's Charles Scanlon in the South Korean capital, Seoul, says there is little expectation of a breakthrough at the talks, but negotiators say this time they will be more flexible and will discuss the problems in more detail.
After the failure of the first three rounds, negotiators fear a further stalemate could derail hopes for a diplomatic solution.
In the 13 months since the last round of talks, North Korea has declared itself a nuclear power.
But it has angrily denied US allegations that it is running a second secret project to enrich uranium in addition to its well-known plutonium programme.
Washington, meanwhile, has been refusing to talk about any kind of pact until North Korea agrees to shut down its nuclear weapons programme.
The US has indicated that the country could face further sanctions if it fails to resolve the nuclear crisis.
Separately, Japan raised the issue of North Korea's abduction of its citizens in the past, although South Korea, China and Russia fear its stance could endanger the negotiations.
In 2002, Pyongyang admitted to abducting 13 people during the 1970s and 1980s, to train spies in Japanese language and culture.
It declared the issue over after repatriating five victims, while saying the other eight had died. However, Japan believes some could still be alive and living in North Korea.
The Russian negotiator, Alexander Alexeyev, has described the Japanese position as counter-productive, though Washington has backed Tokyo.