Jens Stoltenberg said he 'welcomes EU efforts on defence but not as an alternative to NATO' (Picture: PA).
NATO's Secretary General says the defence alliance will become even more important after Brexit as a platform for holding European allies together.
Jens Stoltenberg was speaking after the German chancellor, Angela Merkel, earlier this week, called for the creation of a European Union army.
She said a new military alliance between Germany and France would help realise the creation of such a European force. Britain is opposed to the idea of a European Army.
In an interview with the US network CNBC, Mr Stoltenberg said:
"We welcome EU efforts on defence but not as an alternative to NATO, but something that can complement and strengthen the European pillar within NATO. "
He made the point that "after Brexit, 80% of NATO’s defence expenditure will come from non-EU allies, there is no way the EU can replace NATO."
Most of the money for NATO comes from the US and Canada, Norway and Turkey and after Brexit, the UK.
In an interview with the BBC, he also stressed that any further EU defence cooperation must not compete with NATO and said the alliance would ensure cooperation between defence allies:
"Brexit highlights the importance of NATO because NATO becomes even more important as a platform for bringing European allies together."