On Friday it was announced Mr Cummings, formerly the Prime Minister’s chief advisor, will stop working from Downing Street with immediate effect. According to the BBC he will continue to work from home until the new year.
Lee Cain, Number 10’s communications director, had already announced his resignation.
Prominent EU officials believe the move may lead to a softening of Britain’s negotiating position in ongoing trade talks.
Mr Cummings was the mastermind behind the successful ‘Vote Leave’ campaign for Brexit in 2016.
Manfred Weber, a German MEP and close Angela Merkel ally, told the BBC Mr Cummings departure and the election of Joe Biden increases the pressure on Britain to make concessions.
He said: “I see what is happening now in Downing Street.
“We can see this as a quite chaotic situation where we don’t have any idea what is really the line.
“I think it’s now time for leadership, having all the developments in America in mind, where London has understood it will be not so easy for Boris Johnson to achieve an easy trade deal.
“Now it’s time to take responsibility and come to a common understanding.”
Negotiations between the UK and EU are currently deadlocked over whether Britain will accept a “level playing field on trade” with Brussels.
In practice this could restrict how far Britain is allowed to move away from European regulations in a number of areas.
Speaking earlier this year European Commission President Ursula von der Leyen said: “Without a level playing field on environment, labour, taxation and state aid, you cannot have the highest quality access to the world’s largest single market.”
Mr Weber’s argument was echoed by Philippe Lamberts, who sits on the European Parliament’s Brexit Steering Group and co-leads the faction of Green MEPs.
Speaking to The Times he described the move against Mr Cummings as “probably the sign that Johnson has begun his U-turn and will in the end accept EU conditions”.
However this was dismissed as “simply false” by the Prime Minister’s official spokesman.
He added: “The government position in relation to the future trade agreement negotiations is unchanged — we want to reach a deal but it has to fully respect the sovereignty of Britain.”
Michel Barnier, the EU’s chief negotiator, has been in London this week for talks.
He has said social and environmental policy between the UK and EU must remain “coherent” if Britain is to get a new trade deal.
Though Britain left the EU at the end of January it currently remains in a Brexit transition period with full access to the European single market, but in return it implements a large body of Brussels legislation.
However this will end at the close of this year meaning unless a new trade deal can be agreed Britain will be trading with the EU on World Trade Organisation terms, which would see tariffs imposed.
Contention also remains about the access of European fishing vessels to British waters.
Separately Labour leader Sir Keir Starmer has blasted Downing Street for “pathetic” infighting in the middle of the coronavirus crisis.
He said: “I think millions of people will be waking up this morning, scratching their heads, saying what on Earth is going on?
“We’re in the middle of a pandemic, we’re all worried about our health and our families, we’re all worried about our jobs, and this lot are squabbling behind the door of Number 10.”
