This weekend Poland will choose a new president in an election that will test the government's strength against any resurgence of right-wing populism.

The ruling coalition, led by , has sought to reform Polish democracy after .

But the government has been hamstrung by President Andrzej Duda, an ally of the previous administration, who holds a veto over legislation.

The presidential election - the first round of which is on Sunday - is being billed as a choice between two futures for the EU heavyweight.

If Mr Tusk's ally wins the presidency it could allow the government to push forward with its agenda, while victory for the Law and Justice party may signify a rise of populism in .

Leading the polls is Rafal Trzaskowski, the 53-year-old mayor of Warsaw who was narrowly defeated by Mr Duda in the 2020 presidential vote.

Viewed as a progressive, Mr Trzaskowski's main proposals include increasing defence spending to 5% of GDP, developing Poland's arms and technology industries and liberalising the country's abortion laws.

With Mr Duda unable to run again (presidents in Poland can only serve two terms) the populist side of Polish politics is represented by Karol Nawrocki.

The 42-year-old conservative historian also supports increasing defence spending to 5% of GDP, but unlike Mr Trzaskowski he opposes some LGBT rights and liberalising abortion.

It's a busy field in the first round of the elections (if one candidate does not receive 50% of the vote, the top two go through to a runoff vote, as happened in 2020), with a number of other candidates throwing their hats in the ring.

Among them are the far-right Slawomir Mentzen in third place, who is the speaker of Poland's lower house of Parliament, Szymon Holownia, and three leftwing candidates: Magdalena Biejat, Adrian Zandberg and Joanna Senyszyn.

A key issue in the election is how to build Poland's security in a fast-changing world with waging war on neighbours , according to historian and academic Karolina Wigura.

Poland has been one of the staunchest supporters of Ukraine and boasts a powerful military.

Ms Wigura says the conservative Mr Nawrocki has used anti-Ukrainian rhetoric, similar to language used by the previous government.

Ms Wigura told Sky News: "There is a certain fatigue in Polish society connected with the influx of Ukrainians, which is from the sociological point of view quite natural.

"It happens to every country that welcomes a large group of migrants within a relatively short time."

But Ukrainians are "extremely well-integrated", she says.

Ms Wigura doesn't see much changing in terms of actual policy were Mr Nawrocki to win power. She told Sky News: "I would not expect that the practice of Poland's security system would significantly change. Different rhetoric, but the same core."

Migration and how to prevent it is another key theme going into the elections, with all candidates, including the progressive Mr Trzaskowski, appearing to adopt more robust messaging in response to opinion polls, Ms Wigura says.

"Almost all the candidates, with very few exceptions, tend to argue that Poland should strongly prevent further migration, maybe from the Middle East, maybe from Ukraine or Belarus in general," she said.

Mr Tusk, as well, has been more critical in his comments around immigration.

Earlier this year, Poland temporarily suspended the right of migrants arriving in Poland via its border with Belarus to apply for asylum.

"Unfortunately, it's actually very painful to say that this has been the most racist and antisemitic campaign we have observed in Poland since 1989," Ms Wigura adds.

Poland has one of the strictest sets of laws in Europe when it comes to abortion.

"The 2023 elections were largely won by the democratic coalition because of the ban," Ms Wigura says.

But opinions within the coalition are varied, with so many different viewpoints represented within the government.

It's one of the issues that divides the two frontrunners, with Mr Trzaskowski in favour of liberalising the law and Mr Nawrocki opposes any rollback of recent laws limiting access to abortion.