The US Holocaust Memorial Museum has expressed concern over two legislative initiatives adopted by the Ukrainian Parliament, one of which recognizes the role of a nationalist group accused of committing atrocities against Jews during World War II.

One measure adopted last month establishes an official government commemoration of the Ukrainian Insurgent Army, which some historians believe murdered thousands of Jews in the 1940s. Another bans Communist and Nazi propaganda and symbols.

The legislation is an “attempt to legislate how the history of Ukraine should be discussed and written, especially regarding the Organization of Ukrainian Nationalists (OUN) and the Ukrainian Insurgent Army (UPA),” said a statement issued last week by the Holocaust museum in Washington, DC.

The popularity of UPA, which for a time collaborated with the Nazi occupation to further UPA’s ambitions of sovereignty from Russia, has soared in Ukraine since a 2013 revolution that led to armed conflict with pro-Russian militias in Ukraine’s east.

Enormous suffering was inflicted on Ukrainians and minorities, especially Jews and Poles, from 1917 to 1991 under Soviet and German control, according to the museum. During the periods of control, the ruling countries dictated the narrative of Ukrainian history to suit their needs.

After Ukraine achieved independence in 1991, it opened its archives to scholars in order to study its history.

“As Ukraine advances on its difficult road to full democracy, we strongly urge the nation’s government to refrain from any measure that preempts or censors discussion and politicizes the study of history,” the museum statement said. “Ukrainian democracy must continue on the path of unfettered scholarly research and open debate on all aspects of the national past.”

The UPA leaned towards German Nazis for a time before fighting them as well as the Soviet Union. They are often decried in Russia as “fascist” hardline nationalists.

According to the Yad Vashem Holocaust Memorial Museum in Jerusalem, UPA under Stephan Bandera “considered the Soviets and the Jews their main enemies.”

According to some historical accounts the group murdered thousands of Jews in the 1940s. Other historians, as well as supporters of the UPA, dispute this, claiming there were many Jews who themselves served in the ranks of the organization.

The legislative measures come as Ukraine’s pro-Western government seeks a complete break with its Soviet past and as its soldiers fight rebels in its east allegedly supported by Russia.

Ukraine’s leaders are eager to be seen as reinventing the nation. And erasing all visible reminders of the communist past, they say, is an important step toward that goal.

“Elimination of communism has to happen in people’s heads and consciousness,” said Kiev deputy mayor Oleksiy Reznikov. “Symbolism irritates some people and creates a certain aura that we need to get rid of.”

The laws “prohibit Soviet symbols, condemn the communist regime, open the Soviet special services archives” and officially recognize the role of the UPA.

Besides angering Russia, which has called the move “totalitarian,” the measures rushed through parliament in April also exacerbated tensions with pro-Moscow rebels after lawmakers approved them.

The package of laws bans Soviet flags and means Soviet-era Lenin statues will have to be knocked down and town squares renamed across the country of 45 million people. The laws also ban Nazi propaganda in the ex-Soviet republic.

Penalties for violating the ban range from five to 10 years.

Halyna Coynash, a journalist and member of the Kharkiv Human Rights Protection Group, said some measures risk reverting to the censorship of the communist era. She sees particular danger in a measure that forbids any positive assessment of the Soviet era.

“They have ended up with a law that seriously endangers freedom of speech,” Coynash said.

“Saying that people cannot themselves wear a red star or even have a hammer-and-sickle on their clothing,” Coynash said, “is really quite absurd.”

The campaign against the anti-communist laws has been joined by the several dozen signatories to a letter to Poroshenko pleading with him to reject the bill, which sailed through parliament with little debate.

“However noble the intent, the wholesale condemnation of the entire Soviet period as one of occupation of Ukraine will have unjust and incongruous consequences,” said the letter, which was signed by dozens of international and Ukrainian historians.

The letter argues that the legislation is so loose as to possibly punish anybody writing approvingly of any policies implemented over 74 years of Communist rule.

“Anyone calling attention to the development of Ukrainian culture and language in the 1920s could find himself or herself condemned,” the letter said.

The fate of the Communist leader Lenin’s many statues became the focus of debate during late 2013 protests that led to the ouster of then pro-Russian president Viktor Yanukovych and sparked events that led to the war in the east.

As pro-Western protesters toppled Lenin effigies in rage, pro-Russian separatists in the east gathered at their feet.

Since April 2014, Ukrainian forces have been battling the separatists in a bid to prevent the secession of the Russian-speaking regions of Donetsk and Lugansk.

The West and Kiev have accused the Kremlin of instigating the insurgency and supporting militants with weapons, funds and troops. Moscow has denied the claims.

The intensity of the fighting in eastern Ukraine has declined since a February ceasefire deal but deadly clashes remain frequent.

AP contributed to this report.