Brexit Secretary David Davis says Britain will seek "a deal that works in the best interests of all citizens" in Brexit talks getting under way in Brussels.
Speaking alongside EU chief Brexit negotiator Michel Barnier as they arrived for talks at the European Commission, Davis said he expected "challenging times ahead" in talks expected to stretch for around 16-18 months ahead of the UK's withdrawal from the EU in 2019.
But he said that Monday morning's terror attack in London and the devastating fires in Portugal reminded him that "there is more that unites us than divides us".
"We are starting this negotiation in a positive and constructive tone, determined to build a strong and special partnership between ourselves and our European allies and friends for the future."
Barnier made clear that Brussels intends to stick to its timetable of dealing with the terms of Britain's withdrawal before moving on to discussing future trade relations.
Barnier said the purpose of the talks was to deliver an "orderly withdrawal of the UK from the EU".
"Our objective is clear," he added. "We must first tackle the uncertainties caused by Brexit, first for citizens but also for the beneficiaries of EU policies and for the impact on borders, in particular Ireland."
Barnier said he hoped that during their single day of talks, he and Davis would be able to identify priorities and a timetable for the ongoing negotiations, so that he can report back to leaders of the other 27 EU states at the European Council summit in Brussels on Thursday.
Davis - who earlier said that he was hoping to negotiate a "deal like no other in history" - said the UK was looking for "a new, deep and special partnership with the EU".
