A Labor government would face tough negotiations with the EU Brexitsenior diplomats have warned.
Britain's last EU commissioner and two former British ambassadors spoke out as Sir Keir Starmer will strengthen ties with Brussels if he wins the next general election.
Lord Darroch, the British ambassador to the EU and the US, told the Daily Telegraph: “The Commission is an extremely tenacious negotiator. And they are proud of it.
“The EU has gone further Brexit. There are enough problems throughout Europe. And what happens next with the British really doesn't make the top 10.
“They expect Labor to be fundamentally pro-European, but they also expect Labor to be extremely cautious on Europe [..] we should not expect freebies.”
Sir Julian King, the last British EU Commissioner before that Brexitadded: “Labour must be ready for a very sharp, difficult discussion because just being nice is not enough.”
Sir Ivan Rogers, former ambassador to the EU, warned that “some within Labor tend to vastly underestimate the difficulties they will face”.
Britain and Brussels have agreed to review the agreement Brexit trade agreement in 2026.
Sir Keir had promised to rewrite the deal if he joined Number 10 but was rejected by the EU.
The Labor leader wants a veterinary deal to reduce border controls on the Irish Sea between Britain and Northern Ireland and smoother trade with the bloc.
But Brussels is expected to demand that Britain comply with EU rules on plant and animal health, as well as oversight from the European Court of Justice.
Sir Keir also wants to formalize foreign policy and security cooperation with the bloc, which it is said to be open to.
The Labor leader, who backed Remain and a second referendum, has insisted he will not seek to rejoin the single market or customs union.