EU president Donald Tusk said Wednesday he had cleared his schedule to hold urgent meetings with leaders including Angela Merkel and Francois Hollande to push for a deal to keep Britain in the bloc at a summit next week.

"Let me be clear, this is a very fragile political process. Therefore I have decided to cancel all my obligations and will hold a number of meetings with EU leaders and with the European Parliament in order to help reach an agreement," he told the European Parliament.