With billions of dollars in weapons, the West has sought to give Ukraine the upper hand in its war with Russia. But the dizzying array of arms headed to the battlefield could make it hard for troops to tell friends from foes.

So the US army has come up with a new training tool seemingly designed for the conflict: a set of playing cards with pictures of 52 different Nato-made tanks, armoured personnel carriers, trucks, artillery pieces and other weapons systems, plus two jokers.

The idea, said Major Andrew Harshbarger, a spokesman for the army’s Training and Doctrine Command, is to enable soldiers to quickly “identify enemy equipment and distinguish the equipment from friendly forces.”

The Pentagon has issued similar decks in the past to help forces familiarise themselves with elements of warfare over a hard-fought game of spades, hearts or poker. Each card has a picture of a weapons system, along with its name, the country where it is manufactured, its export destinations and its main armament.

Earlier decks have featured Chinese, Russian and Iranian military equipment. The idea goes back to at least World War II when a pack showed fighter planes used by allies and adversaries. Playing cards depicting the US government’s most wanted Iraqi fugitives, distributed during the American-led invasion in 2003, famously featured Saddam Hussein as the ace of spades.

In a statement, Major Harshbarger did not specifically say the new cards were aimed at helping with Ukraine’s fight against Russia. But he said they could be used across military services, and at all levels up the chain of command.