Polish President Aleksander Kwasniewski has formally asked a leading member of the conservative Law and Justice Party to become Poland's next prime minister.
Kazimierz Marcinkiewicz (left) has two weeks to form a government
Kazimierz Marcinkiewicz was a surprise nomination by the party after winning the elections earlier this month.
Party leader Jaroslaw Kaczynski turned down the job as his twin brother Lech will be standing in the second round of the presidential elections on Sunday.
He said it would be wrong for both brothers to hold the two top posts.
The other candidate in this weekend's presidential election, Donald Tusk, comes from the Civic Platform (PO).
The two parties have been holding talks to form a coalition government, but so far they have made little progress.
In its first session on Wednesday, the newly elected lower house of parliament, the Sejm, failed to elect a speaker.
Mr Marcinkiewicz, 45, has been described as the best choice if the party wanted to "quickly create an effective government".
He has two weeks to submit his cabinet appointments the president and faces a confidence vote in the parliament's lower house within two weeks after that.
The former physics teacher is the head of the parliament's treasury commission and economic adviser for the Law and Justice Party (PiS). His economic competence is widely acknowledged.
His nomination was welcomed by the Civic Platform (PO) which is a pro-business party.
The socially conservative PiS is more welfare-oriented, and Mr Marcinkiewicz has already announced that compromises on the new government's economic policies will be necessary.