Sir Keir Starmer will appear before MPs today as pressure mounts over the appointment of Lord Mandelson as UK ambassador to the US.
The Prime Minister is expected to tell the Commons it was “unforgivable” that he was not informed Lord Mandelson had failed developed vetting checks before taking up the role.
He has said he will make it “crystal clear” to MPs that he had been kept in the dark and promised “full transparency” over the process.
Today’s appearance comes ahead of further scrutiny tomorrow, when former senior civil servant Sir Olly Robbins is due to give evidence to the foreign affairs select committee.
Sir Olly is expected to argue he was unable to disclose the failed vetting outcome because of legal restrictions, a claim Downing Street has strongly rejected.
The Telegraph reports senior Whitehall sources claim Sir Keir had already been warned about concerns linked to Lord Mandelson’s ties to Russia and China through an earlier due diligence exercise, before the formal vetting process took place. The paper says those concerns were similar to issues later raised by UK Security Vetting officials.
No 10 disputes that suggestion, insisting the two processes were fundamentally different and that the Prime Minister was never told security experts had recommended against clearance.
Ministers have also said Sir Keir would have blocked the appointment had he known the result of the vetting checks.