President of the European Council Prime Minister Donald Tusk speaks to journalists as he arrives to the prosecutor's office to testify as a witness in the investigation focusing on the 2010 plane crash that killed President Lech Kaczynski, in Warsaw on August 3, 2017 | Janek Skarzynski/AFP via Getty Images Tusk warns about Poland’s EU future ‘There are several issues where the behavior of the Polish government appears to be very controversial.’

WARSAW — European Council President Donald Tusk questioned Poland’s future in the European Union in harsh remarks Thursday about his home country’s government.

Poland is locked in several disputes with Brussels, including over the Polish authorities’ insistence on allowing trees to be cut down in the Białowieża forest, despite a European Court of Justice order.

“The fact that a European tribunal decision is rejected so arrogantly is evidence of something very dangerous in my opinion — it is an overt attempt to put Poland in conflict with the European Union,” Tusk, a former prime minister, said in Warsaw.

“It smells like an introduction to an announcement that Poland does not need the European Union and that Poland is not needed for the EU,” he said, adding, “I am afraid we are closer to that moment.”

A visibly agitated Tusk warned about what he described as Poland’s weakening position within the bloc. While Tusk’s role is that of a European politician, the current Polish government’s conflict with Brussels over rule of law issues has put him in an uncomfortable position.

“There are several issues where the behavior of the Polish government appears to be very controversial,” he said. “This is how the whole EU sees it and that sometimes even includes Budapest — yes, I mean it” — a reference to Poland's ally, Hungary.

Tusk spoke to reporters in Warsaw after eight hours of questioning at the Polish prosecutor’s office. The former prime minister was summoned to respond to allegations that his government was negligent in its handling of the investigation into a 2010 plane crash that killed many high-ranking Polish officials, including then-president Lech Kaczyński.

Jarosław Kaczyński, the head of the ruling Law and Justice party and the de facto leader of Poland, has painted Tusk as partly responsible for his twin brother Lech’s death. At the same time, Kaczyński now sees Tusk as a potential rival: Tusk will end his term as Council president in 2019, and will be free to run in Poland’s presidential election a few months later.

But Tusk was noncommittal about his future plans.

”I have over two years of work in Brussels,” he said. “I am not able to answer that today but everything is possible. For the moment I don’t plan it.”

He also indicated that he believes he was summoned to testify for political reasons.

“Mr. Kaczyński will not manage to frighten me,” he said to cheers from a few dozen supporters outside the prosecutor’s building. “Neither the prosecutor, nor any other method of teasing me will help him do it.”

He said he expected more questioning in the future and did not exclude the possibility that he would one day testify as a suspect rather than as a witness.

The government is Warsaw sees the judiciary “as a tool against the opposition. And indeed against people they don’t like — I am afraid I belong to this bunch,” he said.