TOKYO: US Secretary of State Condoleezza Rice yesterday called for "de-escalation of tensions" in Northeast Asia following a nuclear test conducted by the Democratic People's Republic of Korea (DPRK) last week.

But US report said satellite data indicated that the DPRK, which has called sanctions imposed last weekend a declaration of war, could be preparing for another test.

Rice, after meeting Japanese Foreign Minister Taro Aso, called the DPRK test "unacceptable," but added that Washington does not want to increase tensions.

"The United States has no desire to escalate this crisis," she said.

"We would like to see it de-escalate."

Rice arrived in Asia as the Bush administration begins a diplomatic campaign to rally international support for sanctions agreed on Saturday. After Japan, she heads to the Republic of Korea (ROK) today and Beijing tomorrow before flying to Russia.

During her visit to China, Rice is scheduled to meet Foreign Minister Li Zhaoxing and other Chinese leaders to discuss the situation on the Korean Peninsula and Sino-US relations, according to the Foreign Ministry.

Aso said yesterday that while the DPRK must return "unconditionally" to the Six-Party Talks aimed at making the Korean Peninsula nuclear-free, political and economic pressure must be coupled with the possibility of talks.

"The window of dialogue remains open," he said.

The UN Security Council resolution over the weekend bans trade with the DPRK in major weapons and materials that could be used in ballistic missile and weapons of mass destruction programmes.

The resolution calls for all countries to inspect cargo to and from the DPRK to enforce the prohibition, although it is not clear how that will work in practice.

Rice said Japan and the US would immediately start examining how to implement the resolution.

The DPRK on Tuesday blasted the UN sanctions, saying they were a declaration of war and that the nation wouldn't cave in to such pressure; and reportedly appeared to be readying another test.

US officials said there has been increased activity around at least two other DPRK sites. The activity, which started some days ago, includes ground preparation at one site and construction of some buildings and other structures, said the official, who spoke on condition of anonymity.

He said although the purpose of the structures is unclear, officials are concerned because the DPRK has left open the possibility of another test.

The ROK yesterday urged restraint.

"We urge the North (DPRK) to recognize the international community's clear and firm position... and not to take any action that is not in line with" the UN resolution, Vice-Foreign Minister Lee Kyu-hyung said.

Liu Jiangyong, a professor of international relations at Tsinghua University, said yesterday that high on the agenda of Rice's China visit would be working out details to implement the sanctions against the DPRK.

"This is a resolution we have to implement," Chinese UN Ambassador Wang Guangya told reporters earlier.

"The question was raised whether China will do inspections. Inspections yes, but inspection is different then interdiction and interception. I think different countries will do it different ways," Wang said.

Liu said that under the current circumstances, interdicting vessels might lead to the escalation of the situation on the Korean Peninsula, or even make it spin out of control.