LONDON — Nigel Farage gave Boris Johnson an early Christmas present — but only half of one.

The Brexit Party leader announced Monday he would stand his troops down in all seats currently held by Tories in the U.K.'s December election. The move marked a significant concession from the 600 he was previously threatening to fight, giving the Tories a Brexit Party-free run at 317 seats.

Having previously dismissed Johnson's deal with Brussels as "Brexit in name only," the announcement effectively acknowledged that voting for the Brexit Party could, in fact, make it less likely the U.K. leaves the European Union.

Spooked by critics, both from within his party and outside, who argued that he risked splitting the anti-EU vote and ushering in a Labour-led government and with it a second Brexit referendum, Farage folded. Last week, he had pleaded with the U.K. prime minister to enter into a non-aggression pact but, with the Brexit Party dropping in the polls, he was forced to take a lonely stand.

"This announcement today prevents a second referendum from happening and that to me is the single most important thing for our country," Farage told activists at a rally in Hartlepool. "In a sense, we now have a Leave alliance, it's just that we have done it unilaterally. We have decided that we will put country before party and take the fight to Labour."

“It would be a mistake to say that this is a completely game-changing moment that means Boris is on course for a huge majority” — Will Tanner, director of think tank Onward

However, analysts question whether the move will have a significant impact on the election because, under Britain's first-part-the-post electoral system, Brexit Party votes are likely to increase the overall share for the Conservatives but are unlikely to translate into many more seats. Polling firm YouGov said the announcement will “likely make very little difference” to the outcome of the election.

Will Tanner, director at right-leaning think tank Onward, said although the decision would help the Tories in the south of England where they were likely to be squeezed by the Liberal Democrats, Labour-held seats in the north and the Midlands, which Johnson will need to win a sizeable majority, will still be locked out of reach.

“It would be a mistake to say that this is a completely game-changing moment that means Boris is on course for a huge majority,” Tanner said. “He still has quite an uphill battle to win lots of the seats he needs to get in.”

Joe Twyman, director of polling firm Datapoll, said Farage had gifted Johnson a problem as much as done him a favor. “I definitely don't think it's great news for the Conservatives, but at the same time it's not perhaps disastrous either,” he said. The challenge for Johnson was always going to be holding onto Remain-voting constituencies while appealing to Leave-voting seats — a near-impossible juggling act, Twyman explained.

Meanwhile, those Labour-held seats, which are historically hostile to the Tories, will be tough for Johnson to win over in the first place, Twyman added. He said potential Brexit Party voters would probably have voted Tory anyway, and appearing to get into bed with Farage will further alienate Remain voters.

Opposition parties were quick to paint Farage's decision as a sign that Johnson's Conservatives back an extreme position on Brexit.

Relief in the ranks

Brexit Party candidates, who had been quietly lobbying Farage to allow Johnson a free pass, breathed a sigh of relief. Wayne Bayley, a retired airline pilot who was set to fight the Tory-held seat of Crawley, said he was pleased. Crawley was won by Henry Smith in 2017 with a majority of just 2,500, meaning Bayley could well have split the pro-Brexit vote and allowed a Labour MP through.

“That risk was unacceptable to me,” Bayley said. “So I am delighted that nationally we will not be taking that risk and can focus our resources predominantly in Leave-voting, northern constituencies.”

But the problem remains: 317 seats is not enough for a majority, and the Brexit Party still risks splitting the vote in scores of marginal Tory targets the party did not win in 2017. Farage's Brexit Party may help the Tories hold on to the seats they have, but they could also make it harder for them to win any more.

But Richard Tice, the Brexit Party chair, MEP and MP candidate for Hartlepool, lashed out at suggestions that the Brexit Party should have gone further in its offer.

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“We've made an unbelievable, unilateral gesture about putting country before party or people,” he told POLITICO. “And frankly, for greedy Tories to suggest that we need to go further is nothing short of outrageous. If they're worried that it's not enough then they should be standing candidates down where they haven't won for 100 years, and they won't win for the next 100, that we can win.”

He added: “This is not about helping Boris Johnson or the Conservative Party. This is about preventing the risk of a second referendum. This provides a base foundation. By doing this there is no prospect of a second referendum happening.”

But Bayley, the former Brexit Party candidate in Crawley, said the target seats the Tories did not win at the 2017 election had become a “gray area.”

“We sorted out the black area and we've sorted out the white area," he argued. "Now there's a gray area that's more nuanced. And I'm sure we all want Brexit, so we aren't going to go and do something that's going to compromise that. I am sure that those conversations will occur and accommodations will be reached.”

If Farage and Tice continue to play hardball, the evidence suggests they could still throw away the Brexit they have long wished for.

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