Poland will order 48 more AHS Krab self-propelled howitzers and 36 accompanying vehicles from local arms producer Huta Stalowa Wola for 3.8 billion zlotys ($797 million), National Defence Minister Mariusz Blaszczak said on Monday.
"This is a second contract, the first was concluded in 2016, and is still being implemented ... the contract value is 3.8 billion zlotys," Blaszczak said.
In 2016, the Polish military ordered 96 self-propelled howitzers from Huta Stalowa Wola to be delivered by 2024.
The AHS Krab has a maximum firing range of 40 kilometres.
Russia's invasion on Ukraine, which Moscow calls a "special military operation" has raised security fears among many former eastern bloc countries, and NATO member Poland has vowed to boost defence spending to 3% of gross domestic product and more than double the size of its army to deter any attacks.
At the end of May, Polish radio said Poland had given Ukraine 18 AHS Krab self-propelled howitzers.