Justice Minister Zbigniew Ziobro announced Saturday that Poland will take the first step needed to withdraw from the Council of Europe's Istanbul Convention on Monday, according to the state-run Polish Press Agency.
The Istanbul Convention, which is the first legally binding treaty of its kind in the world, aims to protect women against violence and to help bring about the end of discrimination against them.
Guy Verhofstadt, the former Prime Minister of Belgium, described Poland's decision as "scandalous" in a tweet on Sunday.
"Violence is not a traditional value. EU and all of its members signed, because Europe stands for human rights, equality and decency," he added.
The Council of Europe Secretary General Marija Pejčinović Burić also disapproved of the country's plan to leave the treaty, calling the development "alarming."
After saying that the Council was happy to engage in "constructive dialogue" with Poland around "any misconceptions or misunderstandings" that may have arisen, she added: "Leaving the Istanbul Convention would be highly regrettable and a major step backwards in the protection of women against violence in Europe."
Speaking at a press conference, Ziobro took aim at what he called the "ideological nature" of parts of the convention, which he accused of "constructing the so-called socio-cultural gender in opposition to biological sex."
Thousands of people gathered in Warsaw and other cities on Friday to protest against the government's plan to exit the treaty, according to Reuters.
Magdalena Lempart, who helped to organize the Warsaw protest, told the news agency that the aim of the move was "to legalize domestic violence."
The announcement from the Justice Minister regarding the withdrawal from the treaty came after Andrezj Duda was re-elected as the country's President earlier this month, narrowly beating the challenge of Rafał Trzaskowski, the mayor of Warsaw.
As part of his campaign, Duda, who is supported by the nationalist ruling Law and Justice (PiS) and is an ally of US President Donald Trump, spoke out against LGBTQ rights, claiming they were an "ideology" worse than Soviet-era communism.
CNN's Sarah Dean and Hilary McGann in London contributed to this report.