Guy Verhofstadt has slammed Brexiteers for their decision to leave the EU single market, claiming it had backfired disastrously and that the UK would most likely seek re-entry to the bloc in the near future.

The former Belgian prime minister has been a vocal critic of Brexit and the UK’s decision to leave the European Union.

He has once again taken aim at Tory hardliners and their decision to go for a hard Brexit.

In an interview with Politico, Mr Verhofstadt claimed the biggest mistake Brexiteers made was to leave the EU’s single market.

“If you cut off your ties with your main export market, you’re asking for difficulties,” he said. “That was clearly said by every economist.”

Brexiteers argued the UK had to leave the single market so the country could be free to strike lucrative trade deals with non-EU countries.

Since Brexit, Britain has signed trade pacts with Australia and New Zealand, as well as joining the Comprehensive and Progressive Agreement for Trans-Pacific Partnership (CPTPP).

Brexit critics claim these deals offer marginal gains at best and in no way compensate for the loss of trade with the EU.

The Office for Budget Responsibility, a government agency, estimates leaving the EU will hit UK GDP by around four percent.

Mr Verhofstadt believes that after the General Eection, the UK will gradually return to the EU fold, a process he claims is already happening.

“I think that more and more after the election we will see a growing pressure to step-by-step to go back in a direction of a more sensible approach,” he said.

“I think what is already happening now will continue. Britain is back in Horizon; tomorrow maybe Erasmus, and after tomorrow the customs union, defence and so on.

“And then later on, maybe people will ask themselves, why are we not in there?

“Because we are following these rules, and maybe it’s better that we have a say about what these rules are.”