Two top US diplomats were set to meet with the Japanese foreign minister Monday after Japan and South Korea pledged to coordinate with Washington over resuming long-delayed talks on North Korea's nuclear program, officials said. South Korea's Foreign Minister Ban Ki-moon, who will be the next UN secretary-general, said that the three countries had worked closely together in the past, and would continue to do so at renewed six-nation disarmament talks expected later this year, according to a Japanese Foreign Ministry official. The official, who briefed reporters after Ban met with his counterpart Sunday in Tokyo, spoke on condition of anonymity, citing protocol. Ban was slated to meet Prime Minister Shinzo Abe on Monday. His trip coincided with visits to Tokyo by US undersecretaries of state Nicholas Burns and Robert Joseph. The two Americans were to meet with Aso and other Japanese officials on Monday before traveling to South Korea, according to Japan's Foreign Ministry. The North agreed this past week to return to the negotiations - which also include China and Russia - in the first easing of tensions after its October 9 nuclear test. The talks have been stalled for a year over financial restrictions placed on the North by the United States for alleged counterfeiting and money laundering. Japanese Foreign Minister Taro Aso said, however, that North Korea's return to the talks "is not a goal in itself," according to the ministry official. Aso said the isolated communist regime must also comply with the UN Security Council resolution passed after its nuclear test and abandon all atomic weapon development. On Saturday, Pyongyang lashed out at Tokyo, saying in a statement that Japan did not need to participate in the talks "because it is no more than a state of the US and it is enough for Tokyo just to be informed of the results of the talks by Washington." Japan is a common target of criticism from the North, stemming from Tokyo's imperial occupation of the Korean peninsula in the early 20th century. Pyongyang has called before for Japan to be excluded from the nuclear talks. Meanwhile, South Korea's Yonhap news agency reported the three allies planned to hold a meeting of their chief nuclear negotiators in Washington as early as next weekend to discuss strategies to move the nuclear talks ahead. The report cited unidentified officials. North Korea said it would return to talks to seek an end to a US-led campaign blocking its access to international banks due to alleged illegal activities such as counterfeiting and money laundering. Washington had said it will discuss the financial restrictions only in the context of the six-nation talks. The North often refers to its nuclear program as a self-defensive measure against the threat of a US attack. Washington has repeatedly insisted it has no intention to attack. The regime's No. 2 leader, Kim Yong Nam, said last week any progress at the revived talks on the communist nation's nuclear program would depend on the United States' "attitude," an indication that a breakthrough could be difficult.