In this connection, a new project began—the Europanzer, which led to the creation of the Leopard 1 for the West Germany or the AMX-30 for France.

[citation needed] In the early 1960s, the Bundeswehr still used American M41s as reconnaissance tanks.

[1] The Ru 251 is based on the Kanonenjagdpanzer tank destroyer and uses the same 90 mm Rheinmetall BK 90/L40 main cannon.

[1] The Ru 251 had remarkable mobility and firepower with its 650 hp Daimler-Benz MB 837 A engine and its Rheinmetall BK 90/L40 90mm cannon, but had no significant anti-tank shell protection.

In 1964, the Ru 251 prototype underwent intensive operational trials, but at the same time the Leopard 1 main battle tank with its 105 mm cannon was prepared for series production.