New Delhi, June 25 -- Ukrainian President Volodymyr Zelensky has warned that Russian President Vladimir Putin could attack a NATO member state within the next five years to test the alliance's unity. In an interview with Sky News, Zelensky said NATO's current pace of bolstering its defences is too slow to deter future aggression from Moscow.

Zelensky argued that while an imminent Russian attack on NATO is unlikely, the risk will increase significantly by 2030.

"We believe that, starting from 2030, Putin can have significantly greater capabilities," he said.

"Today, Ukraine is holding him up, he has no time to drill the army."

The Ukrainian leader said Russian forces are currently suffering heavy losses, adding:

"Russia's soldiers are...