Lawmakers in the European Parliament approved a resolution on Tuesday saying that not enough progress has been made to allow negotiations to proceed to the next level.
The text says that "sufficient progress has not yet been made" in areas including the rights of EU citizens living in Britain, Irish relations and financial obligations to the EU.
It was approved by a vote of 557 to 92 with 29 abstentions, with all major groupings in the European Parliament backing the resolution. Two British Conservative MEPs supported the motion.
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Speaking at the plenary session in Strasbourg on Tuesday, EU Brexit negotiator Michel Barnier told MEPs that there although the negotiation mood improved following British Prime Minister Theresa May's speech in Florence last month, "serious differences" remained — particularly concerning Britain's divorce bill from the EU.
Barnier also rejected accusations from euroskeptic British MEPs that the EU was attempting to hold the UK ransom in the talks.
"There is no ransom, no exit bill, there is only the fact that when you decide to leave we ask you to settle your accounts — no more, no less than to pay what you agreed," Barnier said.
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'Please sack Johnson'
Manfred Weber, the head of the largest group in the European Parliament said that divisions in May's cabinet were blocking Brexit negotiations.
"The top question I think for the moment is: Who shall I call in London? Who speaks for the government — Theresa May, Boris Johnson, or even [Brexit Minister] David Davis?" asked Weber, a member of Angela Merkel's Christian Democrats and the head of the center-right European People's Party alliance in the European Parliament.
Foreign Secretary Boris Johnson and Brexit Minister David Davis, both advocates of "leave" during the Brexit referendum, have sometimes appeared to contradict May's take on some aspects of Brexit.
"Please sack Johnson, because we need a clear answer on who is responsible for the British position," Weber urged. "Theresa May, please don't put the party first — please put Britain first, please put the citizens first."
Trade talks stalled
Although Tuesday's vote was not binding, it reflected EU lawmakers' current mood after four rounds of Brexit talks. The European Parliament will have to approve any final separation deal, currently due for March 2019, or possibly at a later point during a transitional period leaving the EU.
The fifth round of talks is due to start next week, but lawmakers said that "unless there is a major breakthrough," EU leaders should hold off on expanding the talks during their October 19 - 20 summit.
European Commission President Jean-Claude Juncker also said on Tuesday that it was too soon to move on to the next phase of negotiations.
"We first need to agree on the terms of the divorce and then we see if we can half-lovingly find each other again," Juncker told the EU parliament.
Britain has been eager to move on to the next phase of talks in order to start hammering out a trade deal, arguing that it would make sense to discuss these matters in parallel with the EU's priority topics — EU citizen's rights in the UK, financial settlements on exit, and what to do with the Irish border.
Last month, May offered the EU concessions in her speech in Florence on the Brexit bill and called for a two-year transition period after the UK leaves the EU in order to ease the impact on citizens and businesses.
rs/msh (AP, AFP, dpa)