"So help me God," said Tusk, leader of Poland's election-winning liberal party, as he pledged to serve the country, using a formula which, although optional, is traditionally used in government ceremonies in deeply-Catholic Poland. His 18 ministers were then sworn in one by one.

Tusk said his ministers were "well prepared and decent," adding "state power should serve the people, not dominate them." His government intended to focus on "health, wages and home security," Tusk added.

Tusk's Civic Platform (PO) Party beat the conservative Law and Justice Party in a snap election on Oct. 21 and ended the unprecedented political double act of deposed Prime Minister Jaroslaw Kaczynski his identical twin, the president, Lech.

The PO victory also ended the rule of Kaczynski's fractious three-party coalition which had struggled through two years of in-fighting, scandal and criticism.

Tusk hopes for more success with his coalition

Tusk takes over with a new coalition, forced on him due to the fact that Civic Platform missed its goal of obtaining a parliamentary majority, winning 209 of the total 460 seats. He forms his government with members of the moderate Polish Peasants' Party, which won 31 seats in parliament, and has made its leader, Waldemar Pawlak, his deputy prime minister.

Jaroslaw Kaczynski, who formally stepped down as prime minister on Nov. 5, has become the leader of the opposition.

Tusk has pledged to end the regular tussles with the rest of the European Union, and with neighboring Germany in particular, which marked Law and Justice's rule.

He also promised to ease tensions in relations with Russia, which have been at their lowest ebb since Poland broke free from the Communist bloc in 1989.

Rocky times ahead in relationship with US

He has said he will withdraw Polish troops from Iraq, where 900 soldiers are serving in the US-led coalition; and has warned he will drive a harder bargain in talks with Washington on basing part of a US anti-missile system in Poland.

On the domestic side, he has promised to slash bureaucracy, revive the stalled privatization process and reform the health service.

He also wants to spur the already robust economy to try to draw home some of the more than a million Poles who have emigrated since the country joined the EU in 2004.

In addition, he wants Poland to enter the euro zone. The conservatives had regularly expressed skepticism about switching from the national currency, the zloty, to the euro.

EU-friendly Tusk looking to repair European ties

The urbane, amiable Tusk is a dyed-in-the-wool champion of European integration -- and his premiership will be in stark contrast to that of Kaczynski after the fights the brothers picked with EU leaders.

He has also been a confirmed economic liberal since his youth, and has regularly said that Poland needs less state interference and more entrepreneurs.

Besides being an anti-regime activist during communist rule, when he studied Poland's pre-war history, Tusk was a hands-on apprentice in economics, becoming one of the country's few independent businessmen by setting up a small painting firm.

After 1989, when communist rule came to an end in Poland, Tusk and a group of friends in his Baltic Sea hometown of Gdansk founded a political party, the Liberal Democratic Congress (KLD), to campaign for a sweeping privatization of the state-run economy.

In elections in 1991, KLD won 37 seats in Poland's 460-seat lower house, but lost them all two years later, and Tusk opted to merge his party with the larger Freedom Union (UW).

After leading a breakaway in 2001, Tusk formed PO.

New PM looking to reduce state's influence on business

In line with his economic thinking, Tusk is an avowed admirer of the late US President Ronald Reagan and former British Prime Minister Margaret Thatcher.

He has also been a faithful supporter of Lech Walesa, the former Gdansk shipyard electrician who led the communist-era opposition trade union Solidarity and was elected president in 1990. Walesa also backed the PO in the campaign that led to Tusk's victory.

Tusk is proud of his cultural background. He is a Kashubian -- a Slav minority from the Gdansk region -- and has been at the forefront of a cultural revival which has reversed years of decline.

He only discovered his roots as an adult, prompting him to learn the language and later write the first textbook for would-be Kashubian-speakers.