Appearing weary and red-eyed, U.S. Assistant Secretary of State Christopher Hill returned from six-nation nuclear talks in the pre-dawn hours of Tuesday morning here in Beijing.
He said the more than 12 hours he and other delegates invested in the day's negotiations had been time well spent.
"I think we made a lot of progress, so much so, that I think the Chinese felt secure in distributing a final text. But, it has to be approved and so we'll have a meeting tomorrow [Tuesday]."
Hill is the chief U.S. delegate to the six-nation talks, which have been in session since last Thursday. The United States, China, Russia, Japan, and South Korea are trying to agree on a list of actions to begin the process of dismantling North Korea's nuclear programs.
The contents of the draft agreement are not yet public, but are widely anticipated to include and exchange of energy assistance to Pyongyang for a halt in nuclear production.
China had announced that Monday would be the final day of the talks. Delegates from the five partner nations criticized North Korea for unreasonably high energy demands.
However, Hill says Monday's session produced some useful give and take.
"Everybody had to make some changes to try to narrow the differences. Let's get the thing approved, and then we can talk who did what."
Hill says it is now up to the Chinese hosts to secure final approval from all other delegations. Experts say China's role in persuading North Korea is especially crucial, because Beijing is the North's main strategic ally and source of badly needed food, fuel, and trade.
Hill does not rule out extending the talks beyond Tuesday's planned session - if there is momentum.
"In these negotiations, you stay as long as it takes, and as long as you're making progress."
The contents of this week's draft agreement are expected to be published once it has been approved.