KYIV -- It's a measure some Ukrainians claim is necessary to fight Russia's potent "hybrid warfare."

But critics, including Western diplomats in Kyiv, are blasting a moratorium in western Ukraine on all Russian-language books, films, and songs as bigoted and misguided.

Fifty-seven of 84 regional councilors in Lviv, regarded by some as Ukraine's cultural capital, approved the regionwide ban on September 18.

The response has been largely muted within Ukraine, where there are doubts about how energetically it will be enforced, but some influential outsiders are questioning the move.

Canada's ambassador to Ukraine, Roman Waschuk, responded by calling it "just plain dumb."

"The Lviv oblast ban as formulated is narrow-minded, discriminatory and #justplaindumb. And I say this as a diasporic native speaker of Ukrainian, and consistent advocate of affirmative action for cultural products in that language -- but also #diversity," he tweeted.

While Ukrainian is the predominant language in western Ukraine -- especially in Lviv, a province with around 2.5 million residents -- Russian is still widely spoken there.

Russia annexed Ukraine's Crimean Peninsula in March 2014 and has backed a continuing separatist conflict in the country's eastern Donbas region. Moscow has cracked down on pro-Ukrainian activists and closed Ukrainian-language schools in Crimea, and more than 10,300 people have been killed in the conflict, which drags on despite two peace deals and multiple attempts at a cease-fire.

According to the motion, a copy of which was published on the council's website, the moratorium aims to "overcome the consequences of prolonged linguistic Russification" and will remain in place "until the [Russian] occupation of Ukrainian territories comes to an end."

'Playing Into Moscow's Hands'

Moscow justified its invasion of Ukraine by claiming that the government that came to power in Kyiv after street unrest sent Kremlin-friendly President Viktor Yanukovych into exile was discriminating against Ukraine's Russian-speaking population.

Some of Kyiv's subsequent measures appear to have played into its critics' hands. In September, Ukrainian President Petro Poroshenko signed into law a controversial bill that made Ukrainian the required language of study in state schools from the fifth grade on. The bill still allows students to study their native languages as a separate subject.

Some Ukrainian politicians expressed their discontent, including Yevgeniy Murayev, a lawmaker from the For Life opposition party. "As politicians and members of parliament are supposed to do, I speak the state language [Ukrainian] and use it to communicate in matters of the state," he wrote on Facebook.

"But the rest of the time I do not use it in principle," he added, as a sign of protest against what he called the government's "cultural war."

The passage of the moratorium on Russian-language content came as the city of Lviv opened its 25th annual book forum, the slogan for which is "Market of Freedom."

Judith Gough, the British ambassador to Kyiv, joined Waschuk in blasting the move, which she suggested was intolerant. "I couldn't agree more. C'mon Lviv oblast, you're better than this... (And I say this as a fan/student of both the Ukrainian and Russian languages) #tolerance #diversity."

The condemnation from Moscow was particularly fiery. A Russian State Duma deputy and the leader of the nationalist Rodina party, Aleksei Zhuravlev, called backers of the law "animals" and "Russophobes."

"Soon these reactionaries will start to tear out the tongues of their fellow citizens if they decide that a particular tongue is too Russian," he tweeted.

Sergei Tsekov, a member of the International Relations Committee in the Federation Council, Russia's upper house of parliament, claimed the Lviv motion "violates international law as well as the Ukrainian Constitution," according to Russia's state-run RT TV station.

'How Things Have Changed'

Despite the moratorium, it is unlikely that Russian books will disappear from store shelves or Russian films will be inaccessible, especially given their availability online.

The council's motion does not explain how it plans to enforce the moratorium.

The Lviv councilors who supported the measure called on other regions to take similar measures, adding that they planned to appeal to the Verkhovna Rada, Ukraine's parliament, to introduce a bill to ban Russian content across the country.

Ukraine has already banned popular Russian social networks and blocked the import of several Russian books.

It landed in hot water when a history of the Battle of Stalingrad authored by British historian and bestselling author Antony Beevor was discovered to be among them.

Lamenting the decision of the Lviv regional council and perhaps fearing a turning point in Ukraine, Yuliya Komska, the Ukrainian-born author of books about the Cold War and an associate professor of German at Dartmouth University, recalled a time when there was support for language diversity from west to east. It showed itself when a Yanukovych-era law allowing minorities to introduce their languages in regions where they represented more than 10 percent of the population looked set to be repealed in February 2014, she explained in a tweet.

"My hometown, Lviv, switched to Russian for a day, in protest. Donetsk, then unoccupied, to Ukrainian," she wrote. "Things couldn't be more different now."