"However, yesterday, when the Irish taoiseach and the UK prime minister met they both saw, for the first time, a pathway to a deal. I have received promising signals from the taoiseach that a deal is still possible," Tusk said, during a trip to Cyprus.
"Technical talks are taking place in Brussels as we speak. Of course, there is no guarantee of success and the time is practically up. But even the slightest chance must be used," he warned.
The key sticking point in the Brexit negotiations is the border between EU member Ireland and the British province of Northern Ireland, with time running out ahead of Britain´s scheduled departure in barely three weeks.
Barclay and Barnier made no immediate statements after their meeting.
But the Brussels breakfast came after a meeting in northwest England on Thursday, where Johnson and Varadkar said they had "agreed that they could see a pathway to a possible deal".
Speaking to reporters, Varadkar later said the meeting was "very positive", suggesting it would be a "short pathway, rather than a long one".
