There is growing uncertainty that talks on “divorce” issues would make sufficient progress by October, Barnier said, adding that the start of trade talks may be pushed back to December.

EU Brexit chief Michel Barnier (Source: EPA/VNA)

Britain's exit bill, estimated at 60 to 100 billion euros by European sources, has proved one of the biggest sticking points in the negotiations over the UK’s departure from the EU. Earlier, Barnier demanded "clarity" from Britain over its position on the financial settlement needed to meet its obligations under the EU budget.