Jan Cienski in Krynica -

Acting much more quickly than expected, Donald Tusk is swiftly severing his ties to Polish politics and preparing to take up his new job as president of the European Council, leaving his chosen successor to take over his party.

After Tusk's appointment August 31, there had been speculation he would hang on as prime minister for as long as possible before moving to Brussels in early December – possibly leading his Civic Platform party through local government elections on November 16.

Instead, party leaders have raced to accept Tusk's choice to replace him – parliamentary speaker Ewa Kopacz. Tusk now probably plans to resign as prime minister next week, said government spokeswoman Malgorzata Kidawa-Blonska.

Polityka Insight, an analysis firm, speculates that he may use the extra time to polish up his English, as he plans to lead his first conference as Council president entirely in English, a language he has not mastered despite years of private lessons.

Under Poland's constitution, Tusk's resignation would also mean the dismissal of his government. Kopacz will have to be appointed by Bronislaw Komorowski, the president and a Tusk ally, and then will have two weeks to get parliamentary approval for her new cabinet.

Loyal servant becomes master

Kopacz, 58, is a close friend of Tusk who has stood loyally by the prime minister's side as he cleaned the party of his rivals. A doctor, Kopacz has been a politician since the later 1990s. She served as Tusk's health minister from 2007-2011, surviving in a post which has been known to destroy politicians because of public unhappiness with the chronically underfunded Polish healthcare system.

Despite her main job as an increasingly powerful politician, Kopacz still works as a doctor, counting Tusk and his family among her patients.

She has been speaker, constitutionally the third most powerful office in the country, since 2011, where the opposition has accused her of wielding her gavel to favour the ruling party. She was bruised by a scandal after she and her deputies voted themselves juicy annual bonuses, but Tusk stood by his ally and refused to countenance her removal.

Kopacz also shares Tusk's carefully calibrated social liberalism. While insisting that she is a good Catholic, Kopacz does support government financing of in-vitro fertilisation treatment, something the Polish Church hierarchy opposes. She also backs civil partnerships, a step opposed by conservatives who fear it will open the way to allowing gay marriage.

Kopacz's loyalty and similar positions to Tusk on many issues means her government will be one of continuation from Tusk's administration.