Media playback is unsupported on your device Media caption Boris Johnson: UK could have 'great future' outside EU

Boris Johnson has said the UK has a "great, great future" outside the EU if it doesn't secure the reform it needs.

The London Mayor said his preference was to remain part of a reformed EU but is waiting to see the outcome of David Cameron's current renegotiation.

He said: "If we can't get the reform we need Britain has a great, great future elsewhere and outside."

Asked if he could campaign on the opposite side to the prime minister, he said "let's see what happens".

Mr Cameron is currently in Germany as he continues his efforts to renegotiate aspects of the UK's relations with the EU. Once the renegotiation is complete he will hold a referendum of whether or not the UK should stay in the European Union.

Mr Johnson told the BBC Mr Cameron's decision to allow ministers to campaign on either side of the argument had been the "right thing to do", saying people are "a bit internally divided".

He added: "It's something people have different views on, it's a question of principle - how far you think this country's sovereignty should be traded away or shared in exchange for EU membership."

Asked whether he could campaign against Mr Cameron in the upcoming referendum, Mr Johnson said "let's see what happens" and it's a "little bit previous".

He said Mr Cameron was "playing a difficult hand well" but it was important to be "robust" and recognise Germany and others would maintain good trading relations with the UK in any eventuality.

"We've got a good future either way," he added.

David Cameron's four main aims for renegotiation

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