The European Union’s chief Brexit negotiator has reportedly warned that talks on the future relationship between the EU and the UK may be delayed.

The talks were due to get underway in October.

It is believed the warning came when chief EU negotiator Michel Barnier briefed ambassadors from the remaining EU27 nations after the latest round of negotiations wrapped up in London.

Mr Barnier is reportedly worried that Britain had not put forward any position on many key issues up for negotiation.

An EU official was quoted by Reuters as saying that progress was difficult not because Britain had unacceptable demands, but because it had no position on many issues.

The official went on to warn that there have been no detailed talks as yet on the Irish border.

Officials from both sides had previously insisted that the border issue – and finding a solution that does not impose a hard border in Ireland – would form a key part of the talks.

"Barnier expressed concerns that sufficient progress in October looked difficult now,” said the source.

“Mainly because Britain has no position on finances, but also because they don't have positions on other issues as well.”

"The more they drag on, the less time is left for second phase and the special relationship they want."

Following the briefing, another official said they had been warned that the “likelihood of starting the future relationship talks in October appeared to be decreasing."

Brussels is reportedly insisting on sufficient progress around key issues including the financial settlement and citizen’s rights before starting any discussions on the future relationship between the two entities – something Mr Barnier had previously hoped could be achieved by October.

Britain has conceded that it would owe the EU an unspecified amount as part of a financial settlement as it leaves the bloc, but the two sides remain at odds on other issues, including the rights of more than 3 million EU citizens living in the UK and 1.2 million British expats on the continent.

A major sticking point is the role of the European Court of Justice.

Brussels wants the rights of EU citizens already in the UK to be protected by recourse to the European court.

London hopes to reject that demand, insisting jurisdiction should lie with UK courts.

Brexit Secretary David Davis has called for a swift resolution to the citizens' issue, saying it is a "moral imperative."

The next round of divorce talks is scheduled for late August.

Additional reporting from IRN ...