The Northern Ireland Office was “on the side of the Irish government and Sinn Féin/IRA,” during the Brexit negotiations, Boris Johnson’s former top adviser has claimed.

Best known as the mastermind behind the divisive 2016 Brexit campaign and for being at the centre of the political drama that followed the pandemic, Dominic Cummings made the comments on the Quite Right! podcast with the former Cabinet Minister Michael Gove.

First discussing “lawfare” from the UK government against British troops, he talked of how members of the SAS were celebrated for “taking down the IRA” in the 1980s and early 1990s.

“They were given medals for the operations, Mrs Thatcher went and visited them and said ‘brilliant job in extremely difficult circumstances, well done you’re all heroes.’

“The exact same people are now being told in their 70s, ‘you’re going to have to lawyer up and find money from somewhere because you may be facing murder charges.’

He then claimed the Northern Ireland Office was “on the side of the Irish Government and Sinn Féin/IRA” during the Brexit negotiations, as well as stating longstanding elements within Ministry of Defence “which have always hated special forces.”

Former prime minister Boris Johnson pictured with his ex-chief adviser Dominic Cummings (Victoria Jones/PA)Former prime minister Boris Johnson pictured with his ex-chief adviser Dominic Cummings. PICTURE: VICTORIA JONES/PA

“Remember, immediately after World War Two the SAS was closed and other special entities and had to be revived later to deal with various disasters going on.

“So there’s longstanding hatred and opposition to the very concept of British special forces in much of Whitehall.”

Looking back at his time advising Boris Johnson during the pandemic, he said “a complete state failure” made the first lockdown in early 2020 necessary – but subsequent lockdowns could have been avoided if a proper test and trace system was established.

A spokesperson for the NIO said: “We categorically reject these claims.

“They are nonsense and do not reflect the NIO’s steadfast work on behalf of all the people and communities of Northern Ireland.”

Reacting to the interview, the Ulster Unionist MLA Steve Aiken commented: “That perspective of the NIO will not be a surprise to virtually no one.

“The undue influence of the (Irish foreign ministry) is clear to everyone who has sat at various meetings in castles and houses across the land.

“Can’t think of anyone in the UUP or even DUP who thinks differently.”