Poland said Monday it will build a new territorial defence force of 53,000 volunteers by 2019, which it it announced with an eye on heading off any threat from Russia.

Similar to the US National Guard, the force will be made up of civilians who undergo military training. It is intended to deter Russia from seizing Polish territory by infiltration, as it is accused of having done in eastern Ukraine.

"By 2019, the (force) should have 53,000 men," Defence Minister Antoni Macierewicz told a press conference, adding that the new force would cost 800 million euros ($862 million) over the next three years.

But he insisted that the new "units are the cheapest way to increase the strength of the armed forces and the defence capabilities of the country."

"It is also the best response to the dangers of a hybrid war like the one... following Russia's aggression in Ukraine," Macierewicz added, pointing to Moscow's 2014 annexation of Ukraine's Crimean peninsula.

Experts and officials say hybrid warfare is a tactic employed by Russia that uses deception rather than a formal declaration of war.

"Professional soldiers will constitute between six to eight percent of these units and will command the volunteers," defence ministry spokeswoman Beata Perkowska told AFP.

Volunteers who will be paid a nominal sum undergo basic military training and are required to hone their skills on a regular basis.

The first three units of the force will be deployed in eastern Poland, which is deemed to be the most exposed to Russian pressure. Plans call for each of Poland's 16 provinces to have a volunteer force of 3,000-5,000.

The Polish move has been mirrored in the ex-Soviet Baltic states, which have a long history of tension with Moscow.

Poland already has a 12,000-strong paramilitary group, a "riflemen's association" called the Strzelec, first set up in the early 20th century by the architect of Polish independence, Jozef Pilsudski.

NATO leaders endorsed plans this summer to rotate troops into Poland and the three Baltic states to reassure them they would not be left in the lurch if Russia was tempted to repeat its 2014 Ukraine intervention.

The US also said in March it would deploy an additional armoured brigade of about 4,200 troops in eastern Europe from early 2017 on a rotational basis.