Ex-Foreign Office chief Lord McDonald told colleagues he voted to stay in the EU

Former Foreign Office chief Lord McDonald has revealed he told ministers and colleagues he voted to stay in the EU in the wake of Brexit.

Under the civil service code, officials are expected to uphold the fundamental principle of impartiality.

Lord McDonald makes the admission in a BBC documentary series, State of Chaos.

He says: "On this solitary occasion I decided to tell my colleagues and therefore let ministers know that I voted to remain in the European Union."

Asked why he took this unprecedented step, Lord McDonald, who was in charge at the Foreign Office from 2015-2020, says: "I felt they would assume that in any case. So I decided to embrace it."

The civil service code that governs officials' behaviour states that staff are expected to provide impartial advice to ministers and not express their own political preferences.

Laura Kuenssberg: State of Chaos

We've lived through great political turbulence. Laura Kuenssberg asks if our political system has been stretched to breaking point. Can it ever be normal again?

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Lord McDonald says there was a sense of "mourning" and staff in tears in the Foreign Office on the morning after the referendum result.

By revealing his vote, he says he was "trying to convey a message to a group of people, most of whom I felt had voted to remain in the EU, that their personal feelings were beside the point".

He says the board of the Foreign Office were "not entirely comfortable" that he had taken such a rare and unusual step.

In her first ever interview, in the same documentary, the former deputy Cabinet secretary, Helen MacNamara, says in response to Lord McDonald's decision: "Wow… I don't know why that would be a good or helpful thing."

Lord McDonald's comments are likely to anger Conservative Brexiteers who have repeatedly accused top civil servants of dragging their feet during the process of leaving the EU.

Former Chancellor Philip Hammond denied the Treasury tried to block Brexit, but admitted that "the Treasury was certainly trying to go for a soft Brexit and I don't think we should apologise for that at all".

Elsewhere in the first episode of a three part series that traces events from 2016-2022, the former Deputy Prime Minister David Lidington confirms for the first time that there were discussions about him becoming prime minister to replace Theresa May and offer a second referendum.

But he denies the plot would ever have become reality.

"Theresa was not going to go," he says.

You can read more about the series here and watch the first episode on BBC iPlayer.