Prime Minister Theresa May warned British voters on Tuesday that the 27 other EU countries were determined to win a divorce deal that "works for them", using criticism that she had "illusions" over the talks to bolster her election campaign.
After being chided for underestimating the complexity of Brexit talks with the European Union at a meeting in London last week, May said the only way to secure a good deal for Britain was for the country to unite behind her in the snap election she has called for next month.
"We need that strong and stable leadership more than ever before," she wrote in the local Western Morning News newspaper before campaigning in southwest England for the June 8 election, which is expected to see her Conservative Party increase its majority in parliament by more than 100 seats.
"The negotiations ahead will be tough," she wrote. "Across the table from us sit 27 European member states who are united in their determination to do a deal that works for them. We need that same unity of purpose here at home to ensure we can get a deal that works in Britain's national interest too."
After meeting May at her Downing Street residence last Wednesday, European Commission President Jean-Claude Juncker was reported to have said he was "10 times more sceptical than I was before" about the possibility of sealing a deal.
May dismissed the report as "Brussels gossip" and her interior minister, Amber Rudd, told BBC radio on Tuesday that Britain would negotiate more discreetly with the EU.
May's spokesman told reporters the prime minister was confident she could make a success of Brexit and was approaching the talks "in a constructive manner and with huge amounts of goodwill".
Addressing questions about May's capacity to conduct the time-consuming negotiations, he added: "The prime minister is leading the Brexit talks. She will be assisted by the secretary of state for exiting the European Union and senior officials."
The prime minister, appointed shortly after Britain voted to leave the EU last year, has stuck to her policy of revealing little about her negotiating hand before the talks start - most likely after the election.
She has been accused by opposition lawmakers of taking a high-handed approach towards the rest of the EU in the run-up to the talks, potentially poisoning the atmosphere as battle lines are drawn.
May's political legacy rides on the success or failure of the talks. But the EU cannot afford to cut Britain too generous a deal, fearful that Brexit could encourage other members to leave.
With her party still commanding a large lead in the polls despite some gains by the main opposition Labour Party, May again warned voters that any vote for other parties would lead to a "coalition of chaos" that could hurt the EU talks.
"Every vote for me and my local team in this election will be a vote to demonstrate that unity of purpose, to strengthen my negotiating position, and to help me secure the best possible deal," she wrote.
"The opposition parties are lining up to prop up (Labour leader) Jeremy Corbyn and disrupt our Brexit negotiations – a recipe for years of drift and division at this crucial time." (