European Council President Donald Tusk has accused the ruling "Law and Justice" party in Poland of isolating the country in the European Union, noting also the deterioration of relations between Warsaw and Kyiv.

Tusk suggested on Twitter that this party strategy can be part of the "Kremlin plan."

"Alarm! Sharp quarrels with Ukraine, isolation in the European Union, departure from the rule of law and independence of the courts, attacks on the non-state sector and free media - all this is the strategy of "Law and Justice" or the Kremlin's plan? Too much in common to sleep peacefully," Tusk was quoted on Monday by the German Deutsche Welle radio station.

It notes that tense relations between the Polish authorities and Tusk have been running on for several years. Warsaw did not hide its irritation with the re-election of Donald Tusk, the head of the European Council in March 2017.

"There is an attack on Poland under the banner of the European Union," said then the leader of the Polish Conservatives, the head of the ruling party in the country, Jaroslaw Kaczynski.

Tusk, in particular, is accused of making mistakes in organizing the investigation of the plane crash of President Lech Kaczynski near Smolensk in the spring of 2010. In August, Tusk in Warsaw spent eight hours testifying on this case, which he considers "a propagandist campaign" and "an instrument for achieving political goals."

Relations between Poland and Ukraine deteriorated significantly in 2017, including, due to the different interpretations of historical events.