Copenhagen- Danish Prime Minister Anders Fogh Rasmussen is this week due to visit key European capitals, renewing speculation that he was aiming to secure support as future secretary-general of the defence alliance NATO.

Rasmussen has refuted such speculation in the past, saying he still had unfinished work in Denmark and was intent on seeking a fourth term as premier.

Last year, Rasmussen said he would have a busy schedule visiting foreign capitals to shore up support for a successful outcome of an international climate conference to be held in Copenhagen in December.

The conference is seeking an agreement on a new international treaty to succeed the Kyoto Protocol on curbing greenhouse gas emissions.

The premier has also said he wants to oversee efforts to drop the current opt-outs Denmark has from the European Union, including replacing the krone with the joint European currency, the euro.

Although the UN Climate Conference is the official item on the agenda when Rasmussen was Wednesday to have talks with British Prime Minister Gordon Brown in London before flying to Berlin and a meeting with German Chancellor Angela Merkel, Danish media noted the parleys also offered an opportunity for discussions about the future NATO secretary-general.

Rasmussen was Thursday due to visit Brussels to meet with European Commission head Jose Manuel Barroso.

Rasmussen, 56, has been at the helm of government since 2001 when his Liberal Party formed a minority government with the Conservatives, and secured backing from the populist Danish People's Party that has pushed for tighter immigration rules.

Finance Minister Lars Lokke Rasmussen has been widely tipped as his most likely successor should the premier opt to leave Danish politics.

Political commentator Hans Engell, a former conservative politician, told Danish broadcaster TV2 that Rasmussen was a strong contender for the NATO post.

Inger Stojberg, parliamentary group leader of the Liberal Party, ruled out the speculation, underlining that Rasmussen had said he planned to stand for the next elections.

The Danish premier has also been mentioned as a possible candidate for the post that is envisaged under the European Union reform treaty, yet to be formally ratified by all member states. (dpa)