Russia retaliated against tough new Western sanctions on Thursday, banning most food imports from the United States and the European Union and threatening to block flights over its airspace.
The 28-member European Union swiftly denounced the measures -- which also target Canada and Australia -- and said it was ready to take action in response.
The tit-for-tat moves further heighten tensions between Russia and the West over the conflict in Ukraine, where heavy shelling was reported in the rebel-held eastern city of Donetsk on Thursday.
Russia imports 35 percent of the food it consumes and is Europe's second-largest market. Food and agricultural goods account for 10 percent of all EU exports to Russia, which were worth 12 billion euros ($16 billion) last year, according to Eurostat data.
The embargo will affect "imports of beef, pork, fruit and vegetable produce, poultry, fish, cheese, milk and dairy products from the European Union, the United States, Australia, Canada and Norway," Russian Prime Minister Dmitry Medvedev told a government meeting.
The ban exempts only baby food and will last one year unless "our partners demonstrate a constructive approach" with regards to sanctioning Russia, he said.
"I hope that the economic pragmatism of our partners will win over lousy political motives," he said.
People will still be able to buy the banned foods abroad if they want, Medvedev said, warning that those who try to profit from reselling them will be "harshly punished".
Agriculture Minister Nikolai Fyodorov said that restrictions on the "inessential" imports will not hurt consumers in Russia.
The European Commission said the measures were "clearly politically motivated".
"We reserve the right to take action as appropriate," it said in a statement.
In another potential strike against the West, Moscow is considering banning the use of Russian airspace for European airlines, the so-called overflight rights needed to take the shortest route to Asia.
US airlines have not been allowed to use Siberian airspace for years and have been pushing the Russian government to review its policy.
The overflight measure is being mulled in response to EU sanctions effectively grounding Dobrolet, a low-cost subsidiary of Russia's flagship Aeroflot over its flights to Russia's annexed Crimean peninsula on US-made Boeing craft, which EU companies service and lease.
The ban could hurt not only European long-haul carriers but also Aeroflot, which receives the overflight fees.
Bank of America Merrill Lynch estimates that using longer routes bypassing Siberia could add around $30,000 (22,400 euro) per flight to fuel and operating costs.
- 'Not thought through' -
Moscow has billed the sanctions, as well as import restrictions, as good news for Russian producers that will benefit from import substitution and boost production.
Medvedev said the government will work to "prevent price increases" and use the embargo to "clear the store shelves for our producers".
However, economists have warned that the embargo will hurt the poorest Russians, who spend a large percentage of their income on food.
"We could see a minimum of 20 to 30 percent rise in prices, especially for produce," said Igor Nikolayev, who heads Moscow-based FBK Strategic Analysis Institute.
"Substituting imports with Russian food is nothing but tall tales," he said, citing government policies of the last decade which have wiped out farmers with exorbitant taxes.
"To support farmers you need money, but there is no money," he said. Existing money has already been allotted to other needs and Russian state banks can no longer borrow long-term loans on Western financial markets, the economist added.
Analysts have warned that protectionist measures will send inflation soaring because of the higher price for food.
"The protectionist rhetoric from Russia has been gaining momentum," said analysts of VTB Capital in a research note, adding that Russian food prices were already rising.
"There may be shortages of some foods and a drop in quality due to lower competition," said independent analyst Maria Lipman.
"It's such a harsh measure, it's unlikely that everything has been thought through."