Liz Truss has been urged to attend a meeting of European leaders by Brussels’ representative in the UK.
European Union ambassador Joao Vale de Almeida suggested the Prime Minister should attend the European Political Community (EPC) meeting in Prague in October.
He also said Ms Truss’ new administration offered an opportunity to resolve difficulties between Brussels and Westminster as he warned levels of mutual trust had dropped “too low” in recent years.
The European Political Community is Emmanuel Macron’s scheme to bring together EU nations and countries outside the bloc, potentially including the UK.
No 10 is thought to be considering whether Ms Truss or another minister will attend the gathering.
At a fringe meeting at the Labour Party conference in Liverpool, the ambassador said levels of mutual trust between the UK and EU were “too low to be able to produce good results” .
Calling for more regular summits, he said: “Where is the dialogue between our leaders?
“It’s not happening and when it happens it’s not necessarily on a good basis.”
Mr Vale de Almeida said he would “fully support” the presence of Ms Truss at the EPC meeting: “This will be, if it happens, a very good signal in a direction of starting a new cycle, having a mature relationship on issues of fundamental common interest.”
The EU views the Government’s attempts to tear up the Northern Ireland Protocol as illegal and Mr Vale de Almeida said the UK and Brussels needed to remove the stumbling blocks that prevented progress in the relationship.
He said it had been difficult to come to a “sound platform of understanding”.
The message to Ms Truss was to “seize the opportunity that the beginning of a new cycle should provide to reassess where we are and to fundamentally opt for a constructive path forward in trying to find solutions for the problems that have been identified in the implementation of the Northern Ireland Protocol”.
At the event, hosted by the Centre for European Reform, shadow foreign secretary David Lammy said “of course” Ms Truss should attend the EPC meeting in Prague because “these are our allies, our partners”.
He said the Northern Ireland Protocol Bill, which will override parts of the deal signed with the EU on post-Brexit arrangements, was a “kamikaze approach to diplomacy” and warned that if it passed it would risk “a trade war with our closest allies”.
Mr Lammy also defended Labour’s approach to Brexit policy: “I think it’s completely legitimate for us in the Opposition to set out our ambition to solve problems that are emerging but to rule out joining the single market and customs union at this stage “