Senior MEPs have dismissed as “impossible” Boris Johnson’s call for a post-Brexit trade deal to be agreed next month and accused the UK of an “unacceptable” attempt to cherry pick the benefits of European Union membership from outside.

Following talks with Brussels on Monday, the Prime Minister called for a deal to be concluded by the end of July, urging the EU to “put a tiger in the tank” and step up efforts to secure an agreement.

MEPs voted overwhelmingly in favour of a resolution which regretted a lack of real progress in talks so far and highlighted the substantial differences that remained between the two sides.

Major stumbling blocks included the “level playing field” – conditions Brussels demands to ensure fair competition by keeping the UK closely tied to EU standards on workers’ rights, the environment and state subsidies – and fishing rights.

The current transition arrangements expire at the end of the year and MEPs urged the EU to step up planning for a no-deal scenario on January 1.

Senior figures on both sides have said the latest a deal could be reached in order to be ratified in time is the end of October.

David McAllister, who leads the European Parliament’s UK Coordination Group, said: “Let’s put some tiger in the tank but we need to know in which direction the car should drive.

“I’m still hoping the car, in the end, will drive towards an agreement.”

The German MEP, an ally of chancellor Angela Merkel, said: “We hope for the best but, in parallel, we need to step up our no-deal preparations.

“The European Parliament will not agree to a deal at any cost.”

Kati Piri, a member of the coordination group, said: “Beyond a commendable use of idioms, the UK Prime Minister failed to explain how he wants to reach a deal in six weeks, so we are very much looking forward to those details.”

The Dutch MEP said it was “quite impossible to reach a comprehensive agreement in six weeks”.

She said talks were at a “stalemate” due to “very ideological opposite views”.

“We can’t agree on the scope of the agreement and we can’t agree on the legal framework of that agreement,” she said.

Chancellor of the Duchy of Lancaster Michael Gove suggested to MPs at Westminster that the end of October was the real deadline for a deal.

“We don’t have a date per se, pencilled in, but it is the case that if we haven’t secured significant progress by October, then it will be difficult,” he told the Northern Ireland Select Committee.

“I would hope that we would have clarity beforehand, but it becomes increasingly difficult if we are not on a trajectory towards an agreement, increasingly difficult to ensure that that free trade agreement could be concluded if we haven’t secured agreement, as I say, by October.”

The EU’s ambassador to the UK also said the end of October was the deadline for a deal.

“If you do a countdown and if you count the need for ratification time, it means that we need to have a deal by, let’s say, the end of October, which is in exactly four months,” Joao Vale de Almeida said.

Asked if an outline deal could be done by July, Mr Vale de Almeida said: “I think that speed is good. We need to accelerate.

“We need to use every week and every month to try to find a deal.

“But when you drive a car and you speed too much, you can risk falling out of the road, so you need to be careful.

“Because the purpose is not to go fast, the purpose is to get to the destination.”

As the UK approaches the end of the transition period, Politico reported that a “shock and awe” campaign would be launched to prepare the public for the changes on January 1.

The plan forms part of a deal worth up to £4.5 million struck with media agency MullenLowe London, the website said.

Asked about the plan, the Prime Minister’s official spokesman said: “There will certainly be a publicity campaign in order to make sure businesses are aware of the steps that they need to take for us being outside of the single market and the customs union.”

Meanwhile, hopes of a rapid US trade deal, one of the key prizes sought by Brexiteers, appeared to have receded.

US Trade Representative Robert Lighthizer told congress that it would be “almost impossible” for a deal to be reached before the November presidential election and warned that “very, very fundamental issues” had to be resolved.