Donald Tusk led up to half a million people through the streets of Warsaw in one of the biggest demonstrations seen in Poland since the fall of communism.
In a speech to protesters, Mr Tusk, the country’s former prime minister, accused the government of taking away democratic freedoms “piece by piece”.
Warsaw’s council estimated that as many as 500,000 people may have attended, while thousands also took part in demonstrations in other Polish cities.
The march came just days after a new law came into force that critics claim targets Mr Tusk and other opposition leaders in a bid to exclude them from Poland’s general election, which is due to take place in the autumn.
Already dubbed “lex Tusk” the law paves the way for the establishment of a commission to investigate possible Russian influence over Polish politics that in its current form has the power to ban people from public office.
Było nas dziś 500 000🇵🇱
— Donald Tusk (@donaldtusk) June 4, 2023
Opponents fear the commission will be used by the government as a political tool to remove Mr Tusk, a bitter political foe of Law and Justice (PiS), Poland’s governing party, from the election.
In the past, Mr Tusk has faced numerous accusations from Law and Justice leaders of having nefarious connections with Russia when he was prime minister. In particular, his detractors have accused him of deepening Poland’s dependency on Russian energy, although nothing has been proved.
The introduction of the law prompted widespread criticism of it from both within Poland and the US, a key Polish ally, which voiced concerns that it might undermine free and fair elections in the country.
Perhaps stung by its reception, Andrzej Duda, the Polish president, tabled an amendment to the law on Friday diluting some of the commission’s powers, including its right to ban people from public office, despite signing in into power on Monday.
But the amendment will still have to go through a lower house of the Polish parliament dominated by Law and Justice and its allies.