The European Union’s top court could be ruling on British affairs after Brexit while under the influence of mind-bending cannabis, leading Eurosceptic politicians have warned.

The European Court of Justice (ECJ) is headquartered in the tiny country of Luxembourg, whose new coalition government has promised to legalise the recreational use of cannabis.

"If you think some of the ECJ's judgements up until now have been off the wall, just wait for the future when the bored judges are stoned off their heads on wacky baccy,” said Nigel Farage, the MEP and former Ukip leader.

“It's incredible that under Theresa May's Brexit Betrayal proposal that these ECJ judges would still hold sway over Britain."

“Decision in the EU are often made in smoke filled rooms behind closed doors. With the UK leaving the EU, let's hope that smoke won’t be made of something stronger, “ said Daniel Dalton is the Tory MEP for the West Midlands.

Theresa May insists that her Brexit agreement, endorsed on Sunday by EU leaders, will end the ECJ’s supremacy over British courts but critics insist that isn’t true. After the Brexit transition period, the ECJ will give rulings on EU law to a joint UK-EU committee, which must take note of its decision.