Warsaw: Polish Prime Minister Donald Tusk resigned on Tuesday, paving the way for him to take over as European Council president in December.
"I've handed over my papers, that's right," Tusk told reporters in Warsaw when asked whether he had tendered his resignation to the president.
He is likely to be replaced by Ewa Kopacz, dubbed his loyal "Iron Lady" by Polish analysts.
Brussels's choice of Tusk to succeed Herman Van Rompuy in the key EU job is seen in Poland as not only a nod to him, but also a sign of the country's growing political and economic importance within the European fold.
And his governing centre-right Civic Platform (PO) is seeing the first knock-on effects of his presidency, with opinion polls showing it surging ahead of conservative rivals, the opposition Law and Justice (PiS) party.
But it still remains to be seen whether the "Tusk effect" will rub off on the party in legislative elections scheduled for the autumn of 2015.
Tusk, 57, earned the distinction of steering Poland through the global financial crisis as the only European Union member to maintain growth.
As prime minister he also fostered cosy ties with Poland's neighbour, EU powerhouse Germany, in the wake of a frosty earlier episode under a PiS administration.
Tusk has also succeeded in acquiring significant EU subsidies, but critics say that under pressure from various lobby groups he has put off long promised reforms, including a flat tax and slashing bureaucracy.
Once President Bronislaw Komorowski accepts the resignation, he will have two weeks to designate a successor before a September 25 deadline but the president could select a candidate before he makes a trip to Netherlands and the US starting on September 20.
The governing coalition -- an alliance between Tusk's PO and the agrarian Polish People's Party (PSL) -- has already nominated Kopacz, the current parliamentary speaker and an unwavering Tusk ally.
Komorowski said he wanted to maintain the "stability" of government and came out in favour of Kopacz for prime minister. Once he approves her candidature, she will have two weeks to present parliament with a new government and subject it to a vote of confidence.
She is highly likely to get the green light from parliament, given the extent of her backing there.