BIRMINGHAM, United Kingdom: British Prime Minister Theresa May will seek to rally her badly divided party behind her Wednesday as key Brexit deadlines loom, but faces intense opposition to her plans for trade and the Irish border. In her closing speech to the Conservative Party’s annual conference in Birmingham, central England, May will address accusations of a lack of confidence in Britain’s future. “I passionately believe that our best days lie ahead of us and that our future is full of promise,” she will say, according to pre-released extracts of her speech. But the four-day gathering has exposed the continuing splits in the Conservatives over how to approach Brexit, just six months before Britain is due to leave the European Union. Euroskeptic MPs led by former foreign minister Boris Johnson have held a string of packed fringe meetings to argue against May’s plan for Britain to follow EU trade rules on goods. EU leaders have also rejected the overall plan, saying it risks undermining its single market, and demanded London come up with revised proposals by an October 18 summit. May argues her so-called Chequers proposal is the only way to protect jobs and cross-border trade while also avoiding physical checks on Britain’s land border with Ireland. She has however promised new proposals on a plan B — a backstop — to keep the frontier open if and until the new trade deal could be agreed with the EU. Speculation is growing that London may accept some checks on goods passing between Northern Ireland and the rest of Britain, to avoid them on the border with EU member Ireland. But Northern Ireland’s Democratic Unionist Party (DUP) on Tuesday rejected the idea outright. After a meeting with May in Birmingham, DUP leader Arlene Foster tweeted: “NO border in the Irish Sea will ever be acceptable to unionists throughout the UK... regulatory or otherwise.” May’s Conservatives depend on the DUP for their majority in the House of Commons, which must approve any final deal. A rebellion by the DUP, or indeed by even a small number of Conservative MPs, could be enough to kill the deal, potentially causing chaos. May’s hold on power has been fragile since last year’s disastrous snap election when the Conservatives lost their Commons majority. Barely a month has gone by when there is not speculation of a plot against her, much of it focused around Johnson, a leading Brexit campaigner and former mayor of London. He told a 1,500-strong crowd on Tuesday that May’s trade plan was “dangerous,” suggesting it undermined the hopes of Brexit voters. He said Britain was suffering from a “ridiculous seeping away of our self-belief” and said it was not too late to change course if only it had the confidence. Johnson’s speech also ranged from health to housing and crime, in what was widely viewed as a pitch for his party’s leadership. But May has surprised many onlookers by surviving this far, and many delegates here — whatever their feelings on Brexit — are wary of a change at the top now. Johnson himself held back from attacking May in person, while other critics of her EU plan, notably euroskeptic MP Jacob Rees-Mogg, have offered their support for her leadership. The Conservatives are also aware of the threat of the main opposition Labour party, which is only a few points behind in opinion polls and last week presented a radical program at its own conference. Many ministers addressing the main stage in Birmingham have turned their sights on leftist leader Jeremy Corbyn, a theme expected to be echoed by May. She will accuse Corbyn of being divisive, and paint her own party as “decent, moderate and patriotic,” open to “everyone who is willing to work hard and do their best.”