The weapons deal is the largest-ever by NATO-member Poland. The first deliveries are expected in 2022 with the system due to become operational a year later.

The Patriot is a mobile air-defence system made by US defence firm Raytheon with elements from aerospace firms Lockheed Martin and Northrup Grumman. It is designed to intercept tactical ballistic missiles, low-flying cruise missiles and aircraft.

Moscow has complained about the prospect of the deployment of Patriot systems in Poland and Romania, which it says violates a 1987 arms treaty and could be tailored to shoot missiles at Russia.

Tensions with Moscow have been high since the Ukraine crisis and Kremlin's annexation of Crimea in 2014 and the current diplomatic spat over the nerve agent attack on a former Russian spy in Britain has done nothing to calm matters.

NATO ally Romania approved the purchase of a Patriot system worth nearly four billion dollars last November.

- 'Historic' deal -

Warsaw insists the system's deployment as part of its medium-range "Wisla" programme is purely defensive in nature.

"We are signing today a contract to deliver a modern system that has proven itself in numerous countries and thanks to which we are joining an elite group of states which have an efficient weapon that guarantees security," Polish Defence Minister Mariusz Blaszczak told reporters at the signing ceremony at a radar production facility in the Polish capital Warsaw.

In February, Poland's neighbour and NATO ally Lithuania accused Russia of permanently deploying nuclear-capable Iskander ballistic missiles to its Kaliningrad exclave on the Baltic that also shares border with Poland.

Poland's President Andrzej Duda dubbed the missile deal "historic" and told reporters at the signing ceremony in Warsaw that US President Donald Trump said Poland could expect "good terms" during his visit to Poland in July of last year.

Last week Poland signed a 10-year offset deal ahead of the final agreement on the Patriot system under which US investment in Poland will help compensate for the cost of the big-ticket purchase.

Offset deals with Raytheon and Lockheed Martin Global are worth a respective 53 million and 172 million euros.

- Russian adventurism -

US Ambassador to Poland Paul W. Jones on Wednesday called the Patriot deal a "milestone for Poland and NATO", adding that the NATO ally was "joining 15 countries" equipped with Patriot anti-missile systems that are "the foundation of US missile defence and compatible with NATO".

Jones added that "in April we'll begin negotiations on phase two, and in phase two, Poland will get the most modern 360-degree radar, but also more missiles and batteries."

The first phase of the deployment under the contract signed Wednesday provides for the delivery of two batteries with the IBCS system.

These include four AN / MPQ-65 radars, four ECS engagement control stations, six EOC engagement operation centres and sixteen M903 launch systems as well as 208PAC-3MSE missiles and 12 IBCS radio lines.

US Vice President Mike Pence in July raised the possibility of deploying Patriots in nearby Estonia.

Baltic NATO members bordering Russia hope the alliance will agree on additional air defence capabilities for the region during a Brussels summit in July.

Last year, NATO deployed four multinational battalions to Poland and the Baltic states as tripwires against possible Russian adventurism, while the US military sent a Patriot battery to Lithuania for drills.

via/mas/rl

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