The United States does not rule out the possibilities of putting back the Democratic People's Republic of Korea (DPRK) to the list of state sponsors of terrorism, a senior official said yesterday.

"I suppose these things are always possible," State Department spokesman Sean McCormack said at the daily briefing, when asked whether Washington would put back the DPRK to the list of state sponsors of terrorism should Pyongyang takes uncooperative steps on its nuclear program.

"I don't know the ins and outs of the law, but I think that it's based on behavior. And we'll see what behavior North Korea engages in," said the spokesman.

The six parties, namely the DPRK, the United States, South Korea, Japan, Russia and China, all involved in the Korean Peninsula nuclear issues, ended a third day of talks in Beijing without making any progress on the verification of the DPRK's nuclear program.

"I can't say there is any breakthrough," Chief US Negotiator Christopher Hill told reporters yesterday evening in Beijing, adding "It's not trending in the right direction. In terms of coming up with a verification agreement, we don't seem to be narrowing differences."

Under an agreement reached at the six-party talks in February 2007, the DPRK agreed to abandon all nuclear weapons and programs, also promised to declare all its nuclear programs and facilities by the end of 2007. In return, the DPRK would get diplomatic and economic incentives, including its removal from the US list of state sponsors of terrorism.

After its nuclear envoy Hill paid a three-day visit to Pyongyang in early October and struck a verification deal with the DPRK to save the stalled six-party talks, the Bush administration dropped the country from the list on Oct. 11.

But the two countries have disputed over the verification issue, when the US side claims inspectors, according to the deal reached with the DPRK, could take samples away from the nuclear facilities. The DPRK, however, insists that it never agreed to remove the samples.

"They have a unique way of doing business. And we're not going to play into their way of doing business. We know what was agreed. We have it on paper. We have a solid understanding of it," said McCormack.

"Other countries within the six-party talks share that understanding. And we'll see if North Korea will now take final step. And if they don't, then potentially you go down another pathway," he said, adding "We're equally prepared to do both."

"The act of taking them off the state sponsor of terror list was based on fact, was based on the law. The law is very explicit about what gets you on the list and what gets you off the list. There's no cutting corners. You either meet the requirements or you don't," McCormack said.