UN Secretary-General Kofi Annan on Wednesday encouraged the United States to hold bilateral talks with the Democratic People's Republic of Korea (DPRK) either in the framework of the six-party talks or separately.

Annan told reporters at UN headquarters in New York that the United States and the DPRK should talk directly "whether it is done in the context of the six-party talks or separately."

"They did talk in the past. And I think, obviously we have the six-party talks and everyone is urging them to go back to the six-party talks and negotiate very seriously, and I hope the six-party talks can resume," he added.

Meanwhile, the UN chief showed cautious optimism towards the consultation being held in the Security Council, stressing the council should speak with one voice.

"I suspect the council will come together and take a firm action against North Korea," he said. "Discussions are going on, and I hope they will be able to come up with one voice, and decide on measures that should be taken."

However, Annan reminded the Security Council to carefully select the most effective measures so as to bring pressure to the DPRK, and warned the DPRK not to escalate the situation any further in reference to rumors of a second nuclear test.

The secretary-general also pointed out that "the Iranians are also paying attention to what is happening on the Korean Peninsular and what is happening here in the Security Council."

"The parties watch each other. They are all waiting to see how we deal with the respective situations," he said, referring to Iran and the DPRK.

He believed that council members are also very conscious of this, and will bear in mind the broader implication of any actions that they can take.

The Security Council held emergency meeting Monday after the DPRK announced its first-ever nuclear test. After that, council members have been discussing a draft resolution circulated by the United States, which tends to take punitive sanctions against the DPRK.