Conservative MP Boris Johnson walks through his garden at his home near Oxford, Britain, October 3, 2018. REUTERS/Toby Melville

LONDON (Reuters) - Former foreign minister Boris Johnson said on Monday Britain must be able to vary tariffs and strike trade deals after Brexit, otherwise it would not have really left the European Union.

“We must be clear that we can genuinely vary our tariffs and do free trade deals or it will be Brexit in name only and we will betray the British people,” Johnson said on Twitter.