NATO member Poland on Monday invited manufacturers of short-range surface-to-air missiles for technical talks for a planned military revamp amid heightened tensions with Russia.

The defence ministry said the new acquisitions will be part of a planned anti-missile shield and air defence system which is pegged to cost 7.1 billion euros ($8.8 billion).

A supplier will be chosen in 2016, according to officials.

With a population of 38 million people, central Europe's largest country had said last year it would spend 33 billion euros over a decade to upgrade its army.

But Warsaw accelerated the plan after Russia, its Soviet-era master, annexed Ukraine's Crimean peninsula in March and gave backing to pro-Moscow separatist rebels fighting in Ukraine's east.

Warsaw shortlisted French manufacturer Thales and American Raytheon in June for a medium range anti-missile and anti-aircraft system, in a contract valued at six billion euros over a decade.

Polish President Bronislaw Komorowski said in September that Warsaw was "determined to build its missile shield and air defence system... and ... uphold our obligations for the US portion of this project".

NATO's 28 members decided in 2010 to create a missile shield based on US technology. The project is due to be completed in 2020, with significant elements in Poland and Romania.

The Western defence alliance insists the role of the planned shield is a "purely defensive" response to external threats, notably from so-called "rogue states", and is in no way directed against Russia.

But Moscow has taken a dim view of the project, seeing it as a security threat on its very doorstep.

The escalation of tensions with Russia over its role in the Ukraine crisis has sounded the alarm on NATO's eastern flank in countries that were once under Moscow's thumb.

Tensions have mounted further as NATO intercepted nuclear-capable Russian bombers and other warplanes in European airspace on more than 100 occasions so far this year, three times more than in all of 2013.