The 10-year offset programme, under which US investment in Poland will help compensate for the cost of the purchase, is the last stage before the sale of the Patriots.

The minister has said the contract should be signed this month. Pro-government Polish media have reported a date of Wednesday, March 28, for the deal.

"The offset agreements for the Wisla programme are signed. The technology transfer... will strengthen the capacity of the Polish defence industry," the minister wrote on Twitter.

"This is the final step before signing the contract for the delivery of the Patriot system."

The ministry's secretary of state Sebastian Chwalek signed the offset contrat with the US companies Raytheon International and Lockheed Martin Global.

State television TVP Info reported NATO member Poland would pay around 1.0 to 1.3 billion euros ($1.2-1.6 billion) for two Patriot batteries and around 200 of the ground-to-air missiles.

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

The US State Department said in November it had notified Congress of its approval of a larger Poland deal, worth up to $10.5 billion (8.5 billion euros), the first time Warsaw has bought the sophisticated system.

Last July, the two sides had signed a memorandum under which delivery would start in 2022 and the system become operational a year later.

Washington also agreed the US-Israel SkyCeptor missile system, which is expected to be cheaper but still under development, could be integrated into the Polish deal under a second phase.

Last year, NATO deployed four multinational battalions to Poland and the Baltic states as tripwires against possible Russian adventurism.

The Patriot is a mobile air-defence system designed to intercept tactical ballistic missiles, low-flying cruise missiles and aircraft

via-bp/amj

RAYTHEON

LOCKHEED MARTIN