WARSAW (Reuters) -Poland's biggest military parade since the Cold War took place in Warsaw on Tuesday, as the NATO-member country flexed its military muscle in what the government hoped would be both a message to Moscow and to voters ahead of elections in October.

Russia's invasion of Ukraine has made boosting the armed forces a priority for Poland's ruling nationalists Law and Justice (PiS), and with the election campaign in full swing the immense display of military hardware provided a chance to burnish their security credentials.

The Armed Forces Day parade, taking place on the 103rd anniversary of Poland's victory over the Soviet Union in the Battle of Warsaw, saw 2,000 soldiers from Poland and other NATO countries march through the capital accompanied by 200 items of military equipment and 92 aircraft.

"August 15 is not only an opportunity to pay homage to the heroes of the victorious Battle of Warsaw and to thank contemporary soldiers for defending our homeland," Defence Minister Mariusz Blaszczak told troops and onlookers who had gathered near the Vistula river.

"It is also a perfect day to show our strength, to show that we have built powerful armed forces that will effectively defend our borders without hesitation."

PiS, in power since 2015, has vowed to double the size of the army and spend around 4% of gross domestic product (GDP) on defence this year.

President Andrzej Duda, a PiS ally, contrasted what he said was the lack of priority given to defence under the previous government with the investments made in recent years.

"The last eight years have been a time of rebuilding the Polish army," he said. "Earlier we had the opposite situation, a decrease in the size of the Polish armed forces."

Manual worker Dariusz Gawronski, 56, had travelled from the western town of Debno to watch the display.

"The parade gives a very good impression that we have something to defend ourselves with," he said. "I personally feel safe."

However, opposition lawmakers accuse the government of instrumentalising the military for its own political gain.

"I wish you (soldiers)... that you never again have to provide a background for political hatred," Marcin Kierwinski, a lawmaker from liberal opposition party Civic Platform (PO) wrote on social media platform X, formerly known as Twitter.

Duda, Blaszczak and other policymakers including Prime Minister Mateusz Morawiecki looked on as soldiers marched past, while helicopters including Black Hawks and jets including F-16s and FA-50s flew overhead.

Other equipment on display included M1A1 Abrams tanks bought from the United States, South Korean K2 tanks and K9 self-propelled howitzers as well as HIMARS rocket launchers, Patriot air defence systems and Polish-made Borsuk infantry fighting vehicles.

(Reporting by Kacper Pempel, Justyna Pawlak and Alan Charlish, additional reporting by Kuba Stezycki, editing by Angus MacSwan, Alexandra Hudson)