By Philip Blenkinsop and Alastair Macdonald
BRUSSELS (Reuters) - EU chief executive Jean-Claude Juncker blasted Britain's failure to answer "huge numbers of questions" on its Brexit plans as negotiators held a new round of talks on Tuesday on a divorce due in less than two years.
Hours after his chief negotiator Michel Barnier urged his British counterpart to "start negotiating seriously" when they met in Brussels on Monday, European Commission President Juncker echoed the bloc's refusal to discuss the future free trade deal London wants before penciling in terms for leaving the EU.
Juncker scoffed at a raft of British negotiating papers published over the summer which Prime Minister Theresa May's government said had shown London was responding seriously to the detailed proposals agreed by the other 27 EU states.
"I would like to be clear that I did read with the requisite attention all the papers produced by Her Majesty's government; I find none of them truly satisfactory," he told European Union envoys gathered in Brussels for an annual conference. "So there are huge numbers of questions that need to be settled."
These included issues of rights for EU citizens in Britain and Britons in Europe after Brexit and the EU-UK border that will stretch across the island of Ireland, he said.
"We need to be crystal clear that we will begin no negotiations on the new economic and trade relationship between the UK and the EU before all these questions are resolved ... that is the divorce between the EU and the UK," Juncker said.
"We cannot mix these issues up," he continued. Barnier, he said, had firm instructions from the other 27 governments on the phasing of talks, even if he accepted that some issues could not be fully settled without knowing how trade will work.
"First of all we settle the past before we look forward to the future," he insisted.
The head of the European Parliament, Antonio Tajani, joined Juncker in piling pressure on London: "The British government must come forward with clear positions in order for talks to advance," he said in a statement on Tuesday evening.
DEBTS TO SETTLE
Negotiators who began two full days of talks on Tuesday morning are also trying to settle how much Britain may owe the Union on departure - a particularly explosive issue as both sides hope to reach some kind of outline divorce terms this year so as to give time to work out a transition to free trade.
British negotiators, of whom over 100 were taking part in up to five separate forums at the EU headquarters, presented their legal assessment of an EU demand that Juncker has said might leave London paying Brussels some 60 billion euros ($72 billion) - a sum May's ministers have dismissed as unacceptable.
Despite the EU rhetoric, which some in Britain see as ill-judged, government officials played down any tensions and described Monday's hour-long meeting between Barnier and Brexit Secretary David Davis as cordial and constructive.
May's spokeswoman said Britain feels it is in a good position in the negotiations and wants to agree with the European Union to move on to discussions about its future relationship by October, when EU leaders next hold a summit.
"We believe we're in a good position and we would like to move on to discuss our future relationship," May's spokeswoman told reporters.
"We believe that we need the EU to show some more imagination and flexibility when it comes to these discussions," she said. "We are seeking to agree by October Council that we can move to talk about our future relationship."
Davis is due back in Brussels late on Wednesday and to hold a final news conference with Barnier on Thursday to sum up the results of what is the third formal round of talks.