New Ukrainian laws that came into effect over the past two months will outlaw the display of objects and names from the country's communist past, while honoring groups that collaborated with the Nazis in the extermination of Ukrainian Jewry, Bloomberg reports.

A law signed by Ukrainian President Petro Poroshenko last week bans all Soviet and Nazi symbols, including town and street names.

It is expected to lead to the renaming such regional centers as Dnipropetrovsk (named after Grigory Petrovsky, who ran Ukraine in the 1920s and 1930s) and Kirovograd (bearing the name of Sergei Kirov, a Bolshevik leader allegedly killed by Stalin,) as well as dozens of other towns and hundreds of streets.

Another bill, signed into law in April, prescribes that Ukrainians honor a number of World War II nationalist organizations, some of which – such as the Organization of Ukrainian Nationalists and the Ukrainian Insurgent Army (UPA) – fought alongside the Nazis.

The law was protested by 40 historians from major Western universities in an open letter to Poroshenko and Ukrainian legislators.

"Not only would it be a crime to question the legitimacy of an organization (UPA) that slaughtered tens of thousands of Poles in one of the most heinous acts of ethnic cleansing in the history of Ukraine," the historians wrote, " but also it would exempt from criticism the OUN, one of the most extreme political groups in Western Ukraine between the wars, and one which collaborated with Nazi Germany at the outset of the Soviet invasion in 1941.

"It also took part in anti-Jewish pogroms in Ukraine and, in the case of the Melnyk faction, remained allied with the occupation regime throughout the war."

The Organization for Security and Cooperation in Europe also criticized the laws.

“Broadly and vaguely defined language that restricts individuals from expressing views on past events and people, could easily lead to suppression of political, provocative and critical speech, especially in the media,” wrote Dunja Mijatovic, OSCE representative on freedom of the media, in April.

"As Ukraine advances on the difficult road to full democracy, we strongly urge the nation's government to refrain from any measure that preempts or censors discussion or politicizes the study of history," the U.S. Holocaust Memorial Museum said in a statement.