Getty Merkel slams eastern Europeans on migration Chancellor makes emotional plea in closed-door meeting.

STRASBOURG — German Chancellor Angela Merkel harshly criticized eastern European governments for not having learned from their own history in their responses to the migration crisis.

“The eastern Europeans — and I’m counting myself as an eastern European — we have experienced that isolation doesn’t help,” she told members of the center-right European People’s Party Wednesday in a closed-door meeting, according to a recording of the session that POLITICO obtained from one group member.

“It makes me a bit sad that precisely those who can consider themselves lucky that they have lived to see the end of the Cold War, now think that one can completely stay out of certain developments of globalization,” Merkel said, referring to the reluctance of some EU countries to accept refugees.

“It just strikes me as somehow very weird. And that’s why we have to keep talking about that, as friends,” Merkel said, speaking German, as she responded to a question from a Czech MEP on the refugee crisis.

“A rejection [of taking refugees in] as a matter of principle, that is — excuse me for being that blunt — that’s a danger for Europe,” Merkel said.

The German chancellor was emotional in the session, according to the recording and sources in the room. She met with the party group ahead of her joint public appearance with French President François Hollande in Parliament,

The comments come after a turbulent month for Merkel and for the EU over the migration issue, with leaders criticizing her seemingly back-and-forth approach to allowing refugees to enter Germany. Eastern European countries have strongly opposed her policies, and have argued that the EU needs to be tougher in protecting its borders.

Merkel’s demeanor in public is disciplined and reserved, verging on anodyne. But in private, she is known to speak frankly and display a cutting wit. That edge was apparent in Wednesday’s meeting, where she showed a bluntness on the crisis that hasn’t come through publicly in recent weeks.

'This is not Europe'

Less than an hour later, the German chancellor gave a more measured assessment of the crisis in her remarks to the full Parliament. She called for EU countries to work together to better control borders and start to address the root of the problem in the war-torn Mideast .

“We need more Europe," Merkel said in her speech. "We need, more than ever before, the coherence and cohesion that we have shown in the past.”

In the party meeting, Merkel was especially tough on European countries that have portrayed the acceptance of refugees as a threat to religion. “When someone says: 'This is not my Europe, I won’t accept Muslims....' Then I have to say, this is not negotiable.”

European leaders, she said, would lose their credibility if they distinguished between Muslim and Christian refugees. “Who are we to defend Christians around the world if we say we won’t accept a Muslim or a mosque in our country. That won’t do.”

Merkel has provoked a backlash at home and from other EU countries to her approach to migration, first deciding to open Germany’s borders to asylum-seekers, and then shifting gear and imposing stricter controls.

“Yes, we have helped Hungary,” she said in the meeting. “I’m also being criticized for that in Germany. We have helped Hungary because we have thought that one had to save Europe’s dignity.”

Merkel lashed out at Hungarian Prime Minister Viktor Orbán’s government, also for reasons related to Germany’s and her own history. Closing the borders completely would not work, she said: “The refugees won’t be stopped if we just build fences. That I’m deeply convinced of, and I’ve lived behind a fence for long enough,” she said.

“Maybe you can delay it for a couple of years. But even the GDR wall fell, and it fell 25 years ago, and we were all very happy. It just couldn’t be maintained. And so Europe won’t be able to transform into a fortress. It won’t work.”

Specter of Brexit

During the meeting Merkel also said EU leaders should be open to considering important treaty changes if they want the Union to “evolve.”

According to MEPs and officials, Merkel also said during the meeting that the EU treaties should be changed “if necessary” to deal with important issues.

While the discussion focused mainly on the migration crisis facing the EU, the chancellor acknowledged that such treaty changes would be difficult to achieve given the recent history of the EU.

The sources said the mention of possible EU reforms requiring a treaty change came in response to a question from an MEP. They were general in nature and not related to any specific topic, such as the coming British referendum on membership of the Union.

U.K. Prime Minister David Cameron has said that he will push for serious EU reforms in a variety of areas, including policies allowing the free movement of labor and people throughout the Union.

According to several MEPs who attended the meeting, Merkel’s 30-minute discussion touched on a variety of topics besides migration, including negotiations on an EU-U.S. trade agreement, and economic policies.

Merkel’s presentation “showed that changes can be necessary in the EU,” said German MEP Andreas Schwab, “particularly on asylum policies.”

A group of German politicians from her Christian Democratic Union party wrote to Merkel this week to protest her “politics of open borders,” saying they “neither correspond to the European or German law nor does it correspond to the program of the CDU.”

Hans von der Burchard contributed to this article.