"The plan involves the most drastic transformation of the armed forces in the country's modern history," Mitsotakis told parliament.

"The world is changing at an unforeseeable pace," he said.

The drive, which includes a new anti-aircraft defensive dome, is aimed at addressing rapidly changing geopolitical challenges and fraying transatlantic ties, Mitsotakis said.

Greece has traditionally invested at least two percent of gross domestic product in its defence -- NATO's spending target -- owing to decades of tension with regional rivals Turkey.

But the new initiative is also designed to make the country of under 11 million "a key branch" of the European Union's defence mechanism, contributing one of the bloc's "most advanced" armies, Mitsotakis said.