The United States admitted it was not seeing eye-to-eye with North Korea on disarmament issues, as it struggled to persuade the North Korean state to abandon its nuclear weapons programmes and end a three-year stand-off.
Japan said the talks, in their eighth day, were nearing "the moment of truth" and it was up to North Korea to make the next move.
The talks - involving China, Japan, the two Koreas, Russia and the United States - have been hampered by differences about what should be in a Chinese draft document aimed at establishing a framework to rid the Korean peninsula of nuclear weapons.
"I need to be very clear that there are a lot of differences between the North Korean side on one hand and everyone else on the other hand," US envoy Christopher Hill said as he left his hotel for the meeting.
"Frankly we were not able to bridge any differences. I wish I could report more progress from yesterday."
Hill said that although he saw no imminent breakthroughs, the United States was committed to solving the dispute through dialogue.
"We felt the second draft was actually better than the first draft. It clearly reflected the comments of all the parties. And we continue to believe it is a basis for finding an eventual resolution," he said.
In Tokyo, Japanese Foreign Minister Nobutaka Machimura indicated that North Korea was rejecting US demands that it commit itself in writing to dismantling its nuclear projects and admit to having a uranium enrichment programme.
The United States accused North Korea of running a secret uranium enrichment programme in 2000, but Pyongyang has denied this.
Japan's FM Nobutaka Machimura:
N Korea was rejecting US demands
North Korea raised the stakes in February when it declared it possessed nuclear weapons as a deterrent to what it said were US plans to launch a nuclear attack.
Japan's Asahi Shimbun newspaper said Tokyo and Washington also wanted a phrase in the final text stating that Pyongyang had to abandon all its nuclear programmes, both for weapons and civilian purposes.
Its sources said the Chinese and Russian delegates were demanding only that North Korea dismantle its nuclear weapons programmes, the newspaper said.
The fourth round of talks, which came after a break of more than a year, have been the longest since the process started in 2003 and have been characterised by greater willingness from all sides.
Japanese envoy Kenichiro Sasae said on Tuesday that the responsibility was on North Korea to decide what happens next.
"The negotiations seem to be nearing the moment of truth at last," he said as he left his hotel for the talks. "There still remain a lot of differences in the positions of the participating countries.
"The negotiations seem to be nearing the moment of truth at last"
"Today's negotiations will largely depend on moves on North Korea's part."
Machimura suggested the talks might last until the end of this week.
The United States and North Korea, still observing a truce after the Korean war in the early 1950s, have met eight times on the sidelines of the talks in the past week, a breakthrough in itself.
But Hill said they were unlikely to meet again on Tuesday.
North Korea was persuaded back to the negotiating table after a 13-month interval partly by softer rhetoric from the Americans.