As leaders of 29 countries gather in London to celebrate 70 years of Nato, the future of the world’s most successful military alliance remains in doubt.
Nato members will be looking at ways to ensure the grouping is able to survive another decade.
It was founded by the US and Europe in the aftermath of World War II as a defence against Soviet Russia.
Ahead of the summit, Nato Chief Jens Stoltenberg warned Russia the alliance is ready to respond to any attack on Poland or the Baltic countries.
But Turkey on Tuesday said it would oppose Nato’s plan for the defence of Baltic countries if the alliance does not recognise as “terrorists” groups that Turkey is fighting, such as Kurdish militia in Syria.
French President Emmanuel Macron earlier said the world was witnessing the “brain death” of Nato, adding that “strategically and politically, we need to recognize that we have a problem”.
“You have no coordination whatsoever of strategic decision-making between the United States and its Nato allies. None.
“You have an uncoordinated aggressive action by another Nato ally, Turkey, in an area where our interests are at stake,” he said.
Macron said it was crucial to seek rapprochement with non-member Moscow, which regards Nato and its expansion into ex-Communist bloc states with huge suspicion given that the alliance was set up to counter the USSR.
Macron is keen to broker an end to the conflict in Ukraine and has courted President Vladimir Putin as a partner.
US president Donald Trump has long complained that member countries are not meeting their financial commitments to Nato, and has indicated his country is wavering in its support for the alliance.