Viktor Orbán and Jarosław Kaczyński. Hungary and Poland both slid down in the rankings this year | Attila Kisbenedek, Janek Skarzynski/AFP via Getty Images Brexit and Trump encouraged Eastern Europe populism: report Hungary and Poland slide down the rankings, but Kosovo is praised.

The U.K.'s decision to leave the EU and Donald Trump's victory in the U.S. increased fears of instability and emboldened populists in Europe, according to a report out Tuesday by a human rights group.

The U.S. based NGO Freedom House's annual Nations in Transit report found there had been one of the biggest democratic declines across the 29 countries that it monitors in Central and Eastern Europe and the Balkans since it began publishing in 1995.

"Brexit and the new administration in the U.S. have emboldened anti-democratic populists in Central and Eastern Europe and the Balkans," said Nate Schenkkan, project director of Nations in Transit. "A critical mass of leaders in the region openly reject the idea of liberal democracy. Populism increasingly is combining with crude ethnic nationalism in a way that threatens peace in Europe."

Freedom House researchers score countries on a scale of 1 to 7 in seven categories — national democratic governance; local democratic governance; electoral process; independent media; civil society; judicial framework and independence; and corruption — with 1 being the best score and 7 the worst.

Hungary scored the lowest ranking in terms of democracy in the Central Europe region and Poland recorded its lowest score since the project was started.

"Viktor Orbán of Hungary and Jarosław Kaczyński of Poland openly deride the idea that democracy requires independent institutions or constraints on majority rule," Schenkkan said. "There is no more important theater for the defense of democracy than Central Europe."

In the Balkans, Bosnia, Croatia, Macedonia and Serbia all dropped down the rankings but Montenegro and Kosovo's democratic performance improved. Macedonia saw the biggest drop and came close to its 2001 ranking, when "there was violent ethnic conflict in the country."

According to the 2017 report, the "bright spots" were Ukraine, Romania and Kosovo.

"From the lowest starting point in the Balkans, over the past decade Kosovo has made progress towards consolidating statehood and building its own institutions," Schenkkan said.