One of Tusk's main unfulfilled electoral promises is a doubling of the income tax free threshold, with an estimated price tag of some 55 billion zloty ($14.76 billion), coming on top of social benefits already widely viewed as generous.

Poland has elected Karol Nawrocki, a nationalist conservative, as its next president — a win that signals a turn to the right in one of the European Union's member states.

A vote seen as a test of the power of populist nationalism in Europe was too close to call, with exit polls putting the two contenders neck and neck.

Karol Nawrocki, a right-wing nationalist, flipped exit poll results and defeated Warsaw Mayor Rafal Trzaskowski.

One poll has pro-EU candidate Rafal Trzaskowski in the lead, while the other indicates conservative Karol Nawrocki will win.

A runoff election on Sunday pits a centrist against a nationalist who represent mainstream parties. The outcome is unclear given that many under 30 prefer candidates on the political fringes.

Poland's path to narrowing its fiscal deficit, maintaining its credit ratings and keeping investors on board looks more difficult following conservative nationalist Karol Nawrocki's presidential election triumph.

“In the first round of the election, you had only 60 percent of people voting for the two strongest candidates,” Buras said. “That was the lowest joint result of the two top candidates in the history of Polish presidential elections. Which means many ...