The message from the Brexit party MEP John Tennant could hardly have been clearer: Boris Johnson’s departure deal is “a trap” and must be voted down at all costs. But within a few paragraphs the tone changes. “It’s still a Brexit of sorts,” Tennant writes, now saying he will reluctantly support it.

A leaked email that Tennant sent to aides this week appears to show two versions of a script for a video message to be released after the European parliament’s vote on the Brexit deal on Wednesday.

The leak highlights the dilemma facing Nigel Farage’s party before what is likely to be the last significant political moment of its brief and tumultuous existence.

In the first version of the script, Tennant, one of 29 Brexit party MEPs elected in May, argues for opposing the planned deal and holding out instead for a no-deal departure. “This deal isn’t worth the paper it’s written on. It’s a trap,” he writes. “I know we probably don’t have the votes to vote this deal down, but if it did fall there would once again be a slim chance of a genuine clean-break Brexit on 31 January.

“It’s like we’re a goal down, sending the keeper up in the 93rd minute for a corner kick. There’s not much chance of it succeeding but we’ve got to try. Call it my last stand, call it Brexit’s last stand, but I’ve got to at least try to vote it down.”

The next script is still deeply sceptical of the plan, calling it “the second worst deal in history” – second only to Theresa May’s version – before abruptly changing tack. “But here’s the thing,” Tennant writes. “It’s still better than not leaving this hideous place at all. We will – mostly – get back control of our borders. We’ll get our own independent trade policy back. We’ll stop giving the EU billions of our hard-earned cash. That has to still count for something.

“It’s still a Brexit of sorts. However bad the deal is, I couldn’t in all conscience vote against Brexit. How could I deny reality and jeopardise the only Brexit that’s still reasonably possible at this stage?”

The two-script approach echoes Johnson himself, who famously drafted two newspaper columns, one pro-Brexit and one supporting remain, before opting to pick the leave side.

A Liberal Democrat source said: “The Brexit party have been on somewhat of a learning curve this week, from discovering that leaving the EU means losing our seat at the table to now their indecision on whether to even back the Brexit bill. Like Boris Johnson and his two letters, it’s clear they can’t have ever had the country’s interests at heart.”

Farage began the general election campaign insisting he could only back a no-deal Brexit, but then stood down candidates in 317 Conservative-held seats, saying he had been reassured by Johnson’s pledges over the departure.

A week before the election, three Brexit party MEPs switched to the Conservatives, saying only Johnson could deliver Brexit.

A Brexit party spokesman said Tennant had simply been “drafting ideas” in much the same way as Johnson did. “There are good points and bad points to both choices, he still hasn’t reached a conclusion, but will do before next week’s vote,” the spokesman said.