As recent years have seen many nations turn inward, German President Frank-Walter Steinmeier was in Poland on Friday in a bid to promote pro-EU enthusiasm in a country controlled by the nationalist right-wing Law and Justice (PiS) party.

Relations between Poland and Europe have been further strained over a series of controversial reforms implemented by PiS since the party took power in October 2015. Last year, the European Commission said that it was investigating the Polish government for breaching EU regulations.

The probe is in response to a raft of measures curtailing media freedom and several controversial appointments to the country's Constitutional Court.

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Steinmeier sought to act as a bridge between Warsaw and Brussels during talks with his Polish counterpart, Andrzej Duda. The German president said that international upheaval "made it all the more necessary" for Europe to stand together for "democracy, freedom, the rule of law and an open society."

"For me it's clear that Poland belongs to the core of Europe and Poland will be needed if we are to overcome this crisis that we are no doubt in," Steinmeier added. With Berlin and Paris considered the two main pro-EU governments left in Europe, Germany is attempting to repair cooled ties with its more skeptical neighbor.

 "The crisis did not start with Brexit but without a doubt it has gotten deeper with Brexit, and that makes it even more important that the 27 of us stick together, and we need Poland for that," the German head of state said.

'We have to work together'

Duda agreed that "we have to work together," to resolve the issues between Warsaw and the European Commission and suggested a summit not only of German and Polish leaders, but also including the government of newly inaugurated French President Emmanuel Macron.

Foreign Minister Witold Waszczykowski struck a slightly more cautious tone in an interview with German daily Welt. The top diplomat said that while he considered Berlin a "reliable partner," all EU nations "have the right to pursue their own interests."

Steinmeier was also set to meet with Polish Prime Minister Beata Szydlo. One of her first decisions upon taking office was to remove the EU flag from the background of her press conferences. Furthermore, she has accused the European Union of trying to blackmail Poland with its investigation. Her rule has sparked widespread protests across the country over everything from new media regulations to proposed restrictions on abortion.

es/rt (AFP, dpa)