European Council president Donald Tusk has said the EU 27 must "remain united" as leaders of the 27 European countries meet in Brussels to ratify its guidelines for forthcoming negotiations with the UK.
Arriving at a special summit in Brussels, Mr Tusk restated his view that the EU must first focus on the terms of Britain's exit from the EU, the status of EU nationals in the UK, and the status of Northern Ireland, before considering any future trading arrangements.
"We need to remain united as the EU 27," he said.
"It is only then that we will be able to conclude the negotiations which means that our unity is also in the UK's interest.
"As for now I feel strong support from all the EU institutions, including the European Parliament, as well as all the 27 members states.
"I know this is something unique, but I am confident that it will not change."
Mr Tusk published his draft negotiating strategy last month.
There are unlikely to be any radical departures in the final framework, with the EU 27 expected to remain firmly committed to a "phased" approach to negotiations.
Mr Tusk has insisted "significant progress" must be made on disentangling the UK from its ties and obligations to the EU before discussions can turn to the post-Brexit relations.
Mr Tusk told waiting journalists: "We all want a close and strong future relationship with the UK - there is absolutely no question about that.
"But before discussing our future we have to sort out our past, and we will handle it with genuine care, but fairly.
"This I think is the only possible way to move forward.
"We also need solid guarantees for all citizens and their families who will be affected by Brexit on both sides.
"This must be the number one priority for the EU and the UK.
"And the Commission has already prepared a precise and detailed list of citizens' rights we want to protect."
