South Korea will transfer the expertise needed to build K2 tanks to Poland, the countries' defence ministers said Thursday, a key step towards production inside the territory of Ukraine staunch ally.

Since Russia's invasion, NATO member Poland has signed contracts worth $12.7 billion to buy South Korean weapons including tanks, artillery and fighter jets.

In 2022, Warsaw made a first order for around 200 K2 "Black Panther" battle tanks built by Hyundai Rotem.

But it is scheduled to acquire more than 800 of a special variant called K2PL, to be produced in Poland.

Seoul's transfer of the manufacturing technology marks progress towards Poland's ambition to begin making the tanks itself from 2026.

"Yes, we will manufacture (tanks) in Poland," Defence Minister Wladyslaw Kosiniak-Kamysz told journalists in Pruszkow, near Warsaw.

Speaking alongside his South Korean counterpart Shin Won-sik, Kosiniak-Kamysz added that the transfer for "the preparation of Polish arms factories for this project will take place immediately".

Though the first deliveries have already begun, Poland is still negotiating the terms of the financing, delivery, servicing and in some cases production of the equipment with South Korea, said Kosiniak-Kamysz.

"But I think that after today's discussion, a positive conclusion with conditions that the Polish side will be able to accept is very close."

Besides the 1,000 K2 tanks, Poland ordered 288 K239 Chunmoo multiple rocket launcher systems, 672 K9A1 self-propelled howitzers and 50 FA-50 fighter jets from South Korea.

These purchases made Warsaw the largest buyer of South Korean armaments in Europe, according to specialist website Defense News.

A neighbour of both Russia and Ukraine, Poland argued it needed to step up its arms purchases to deter aggression.