"Only when we are united can we successfully perform even the most difficult issues and tasks," said Tusk, the EU's Council President. "I have no doubts that the real test of our unity will be the second phase of the Brexit talks."
Brexit talks due to get green light to move on to trade →
Tusk noted that Britain has asked for a two-year bridging period, he laid out conditions for that to happen.
Britain, EU in Brexit breakthrough; eye talks on future ties →