NATO head Anders Fogh Rasmussen Monday welcomed an agreement due to be signed with Tokyo pledging Japan's continued cooperation in the fight against "emerging security challenges".

Secretary General Rasmussen, a former Danish prime minister, said he would be meeting Japanese Prime Minister Shinzo Abe later in the day to issue a joint declaration on closer NATO-Japan partnership.

Thanking Japan for its past support, including in anti-piracy operations in the Gulf of Aden off Somalia and in the reconstruction of Afghanistan, Rasmussen said: "So how can we build on these experiences?"

"How can NATO and Japan deepen and broaden their relationship in the future to help make the world safer for all of us? First and foremost, we should continue to intensify our political dialogue," he said.

"And I am delighted that later today, Prime Minister Abe and I will sign a joint political declaration to guide our future work."

The declaration highlights cooperation in managing crisis situations including natural disasters and "emerging security challenges -- terrorism, cyber attacks, piracy, and the proliferation of weapons of mass destruction and their means of delivery", he said.

Rasmussen said after NATO troops leave Afghanistan in 2014 the alliance wants to continue training and assisting Afghan security forces.

"I very much hope that Japan will continue its support for the efforts of the international community in Afghanistan."

Japan has never had a combat role in Afghanistan, but has been involved in reconstruction and is a major donor.

Japanese naval ships returned home in early 2010 at the close of an eight-year refuelling mission in support of US-led military operations in Afghanistan at a time of strains in the US-Japan alliance.

Japan last year hosted an Afghan aid conference, where donor nations pledged $16 billion for Afghanistan to prevent the country from sliding back into turmoil when foreign combat troops depart, but called on Kabul to implement reforms to fight graft.