Russian authorities are expanding their crackdown on McDonald’s restaurants by making more food safety checks a day after four branches of the fast-food chain were shut down.

The country’s food safety agency temporarily shuttered the four branches in Moscow for breaching “numerous” sanitary laws.

RIA Novosti and Interfax on Thursday quoted Natalya Lukyantseva, an official in the Sverdlovsk regional office of the agency, stating that checks were being carried out in a number of restaurants in the Ural region in central Russia due to customer complaints.

The move comes in light of increasing tensions between Russia and Western countries over the situation in eastern Ukraine.

The U.S., Canada and European Union have all imposed sanctions on Russian banks, banned food imports from Russia and other industries last month.

Russia  Sanctions

A woman shops at a supermarket in downtown Moscow on Thursday. Russia's new sanctions were made in response to sanctions imposed on Russia by the West over the crisis in Ukraine. (Ivan Sekretarev/Associated Press)

And earlier this month, Russia imposed a "full embargo" on food imports from the EU, US, Australia and Canada. So far, no other major Western chains have reported any such activity.

Amrest, company that holds the of the Russian franchises for several other U.S. brands such as Starbucks, Pizza Hut, Burger King and KFC has said it was experiencing no problems.

"Obviously, it's driven by the political issues surrounding Ukraine," Alexis Rodzianko, President and CEO of the American Chamber of Commerce in Russia, told Reuters. "The question on my mind is: Is this going to be a knock on the door, or is this going to be the beginning of a campaign?"

McDonald’s posted on its website Wednesday that it was doing as much as it can “for a speedy opening” of the four Moscow restaurants.

A spokeswoman told The Wall Street Journal that serving “top-quality food remains our main priority” but did not speak further about the issue.

The fast-food giant first opened its doors in Russia in 1990 and now has 435 restaurants across Russia, employing 12,000 people.

With files from The Associated Press and Reuters