Munich (Agencies): Monitoring turmoil in the Arab world, NATO’s chief Anders Fogh Rasmussen rebuked European governments over their shrinking military budgets, warning that it would leave Europe weaker in a fast-moving world.

Secretary General Anders Fogh Rasmussen cautioned that a dramatic cut in defence spending would seriously diminish Europe's ability to respond to crises and risked alienating the United States.

"As I speak, fast-moving events are unfolding in Egypt, Tunisia, and elsewhere in the Middle East and North Africa," Rasmussen told the Munich Security Conference, an annual meeting of leaders in the defence field.

"The outcome of this turmoil remains unclear, its long-term consequences unpredictable. But one thing we know: old certainties no longer hold, tectonic plates are shifting," he said.

The United States accounted for just under half of NATO's total defence spending 10 years ago, but the country's share has grown to 75 per cent today, the head of the 28-nation alliance said.

"At stake today is not just the world economy, but the world order. So why, now of all times, should Europe conclude that it no longer needs to invest in defence?"

Defence spending by NATO's European members has decreased by 45 billion euros over the past two years, the equivalent of Germany's entire annual budget, Rasmussen said.