EU and British negotiators say the first day of negotiations on Britain's departure from the European Union was productive in outlining the program ahead and setting out the first challenges to settle, especially the rights of citizens living on each other's territory.
"We must first tackle the uncertainties caused by Brexit", centering on citizens living on each other's territory, border arrangements between Ireland and the United Kingdom and the amount that Britain stands to pay to get out of its previous European Union commitments, Barnier said.
The agenda for the meeting was agreed earlier this month following preparatory "talks about talks".
Monday morning's terror attack in London and devastating fires in Portugal reminded him that "there is more that unites us than divides us".
"In the first step, we will deal with the most pressing issues". An early election this month, in which British Prime Minister Theresa May lost her Conservative majority in parliament, only added to the problems. "It's a statement of common sense that if we are going to radically change the way we work together, we need to get there via a slope, not a cliff edge".
Rejecting the Prime Minister's "no deal" mantra, Hammond said that his position was one of a "jobs first" Brexit.
Still, the May's government said in a statement it was "confident it can achieve a bold and ambitious deal that will work in the interest of the whole United Kingdom".
Mr Barnier made clear Brussels intends to stick to its timetable of dealing with the terms of Britain's "orderly" withdrawal before moving on to discussing trade relations.
Davis, who has previously said the discussion timetable would be "the row of the summer", is expected to initially accept the EU's approach, although a spokesman for his Department for Exiting the European Union said: "As the European Union has itself said, 'nothing is agreed, until everything is agreed'".
Sandro Gozi, Italy's European minister, had new doubts about Britain's negotiating position since the election result.
Both EU negotiator Michel Barnier and his British counterpart David Davis said after the first negotiating session they were confident of quick progress but said major challenges lay ahead to meet the deadline of March 2019 for Britain to officially leave the bloc.
Johnson also urged Europeans to look further down the road.
Last year's Brexit vote came as a profound shock to Brussels against a backdrop of rising anti-EU sentiment, with many - including now US President Donald Trump - predicting the bloc's eventual break-up.
Germany's deputy foreign minister, Michael Roth, told RBB Inforadio that "we must of course protect our interests as the European Union 27 but naturally we also don't want to punish Britain".
"It seems freakish to press on before the government is secure in its ability to command a Commons majority and before the Queen's Speech, but the United Kingdom has to show willing - the dithering has to stop". He said he views the talks with "informed optimism". The EU wants to secure cash and rights for citizens immediately and is not willing to mess around. The group said any deal should minimize trade barriers and include a flexible immigration system. He added: "Brexit won't make anything better, but it will make a lot of things more hard".