Russia's president Vladimir Putin has announced a ban on imports of agricultural and food products from countries including the US, EU, Canada, Australia and Norway in reaction to sanctions imposed against it by these countries.

The Russian government approved a list of food products – which includes pig meat – covered by the ban, which was effective immediately.

Imports of beef, pork, poultry, fish, cheese, milk, fruits and vegetables from the US, EU, Canada, Australia and Norway will be banned for a period of one year, Russia's Prime Minister, Dmitry Medvedev, announced.

Brazil is understood to be in discussion with Russia with the view to filling the gap in supply left by the ban.

Pig producers in Canada have expressed concerns about Russia's imposition of the ban on its pig meat.

US pork exports remained strong in June, pushing export value to a record pace for the first six months of the year.

According to statistics released by USDA and compiled by the US Meat Export Federation, June pork exports totalled 181,531 tonnes, up seven per cent from a year ago, while export value increased 25 per cent to $585.1 million. In the first half of 2014, pork export volume (1.15 million tonnes or +9 per cent) and value ($3.4 billion, +17 per cent) broke previous records.

Russia already has a ban in place on US pork exports for other reasons, and so the latest announcement will not directly affect that sector. It may, however, lead to additional competition in other markets as the EU and Canada seek alternative destinations for their pork.

Farmers in the European Union will be protected from the worst impacts of the Russian ban, according to EU Commissioner for Agriculture and Rural Development, Dacian Ciolos. He has said that the Common Agricultural Policy (CAP) should help to protect farmers.

He said: "I understand the concern expressed in the EU farming sector. I want to underline that the Common Agricultural Policy has new and modernised tools to stand by them, as soon as it is needed, including our crisis reserve, which is already available now.

"I am confident that our resilient farm sector will reorient rapidly towards new markets and opportunities. But there must be support to help this transition happen smoothly. This requires a joined-up, European response."

New outbreaks of African swine fever have been reported in the last week in Russia, Poland, Latvia and Lithuania in both wild boar and domestic pigs. Officials from the Baltic states and Poland have agreed on measures to combat the spread of the virus.

The US veterinary authority has not yet released its latest weekly report on Porcine Epidemic Diarrhoea. Recent outbreaks have been reported in Japan and Mexico but there have been no new cases in Canada since 21 July.