The Sun has quoted unnamed EU sources as saying that UK Prime Minister Boris Johnson's chief adviser Dominic Cummings is behind Britain's no compromise stance on post-Brexit talks with Brussels.
They claimed that Cummings is "pressuring UK negotiators to stick firmly to their red lines to get the best Brexit deal possible".
The sources also referred to Oliver Lewis, the UK's deputy Brexit negotiator and a close ally of Cummings, describing him as a key hurdle in the talks and dubbing Lewis "the political commissar".
Some EU insiders also singled out increasing concern over Vote Leave supporters in Johnson's inner circle pushing for a "pure" no deal scenario.
London has, for its part, repeatedly denied speculations that any of the PM's team may try to block the post-Brexit talks.
The claims come after EU chief negotiator Michel Barnier reportedly signaled a readiness earlier in July to prepare the ground to soften his hardline stance on the talks if Johnson shows a willingness to arrive at a consensus.
"The UK can't wait too long to compromise. Barnier is now preparing our side for a different outcome. I don't think Johnson has prepared his", one of the sources was cited by The Sun as saying at the time.
In late May, the chief EU negotiator told The Times that the UK may face a no-deal Brexit if Johnson fails to deliver on Britain's commitments pertaining to the political declaration that London signed with the European Commission.
Barnier warned that there would not be an agreement "at any cost" and that "the UK has been taking a step back — two steps back, three steps back — from the original commitments".
The two sides remain at odds over the post-Brexit trade talks as Barnier and his UK counterpart David Frost blame each other for the current stalemate. The EU chief negotiator insists that a "new dynamism" is needed in the negotiations, while Frost argues that Brussels' proposed deal "contains novel and unbalanced proposals which would bind this country to EU law or standards".
The UK officially left the European Union on 31 January, after years of negotiating for a deal with Brussels that would get the approval of the British Parliament. Brexit was postponed on several occasions, with Johnson initially planning it for 31 October 2019. The UK is set to go through a transition period to negotiate new trade deals with other countries, as well as the EU, now being outside the European Customs Union.