Sir Keir Starmer is set to appoint a diplomat who left sensitive top secret files at a bus stop as Britain's ambassador to Nato.
Angus Lapsley lost a 50-page classified file which held the locations of British special forces in Kabul, Afghanistan, and the Royal Navy's movements in the Russian-occupied Crimean peninsula, in June 2021.
The dossier included one document marked "secret, UK eyes only" and others labelled "official, sensitive".
Despite the error, Lapsley kept his job in the civil service and was later promoted from the Foreign Office to Nato in 2022, where he was made the assistant secretary-general for defence policy and planning.
More recently, he has worked on Britain's crucial strategic defence review.
Lapsley, according to The Times, is set to take over from Sir David Quarrey, who has been the UK's permanent representative to Nato since April 2022, next week.
One senior defence source who worked with Lapsley in the past said: "It is deeply worrying that the Foreign Office and Ministry of Defence don't take security seriously."
He had been tipped for the ambassadorship before the security breach - but defence sources have said that he is now expected to take it up in just days.
But officials have remained coy - a Ministry of Defence spokesman told The Telegraph that Lapsley was still working on the strategic defence review and that there were no plans for that to change.
While a Foreign Office spokesman said: "Ambassador appointments will be confirmed in the usual way."
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Reeves: 'I wasn't aware that previous Chancellors had released their tax return'
Rachel Reeves has now said that she 'wasn't aware that previous Chancellors had released their tax return'
PA/HMRC
Rachel Reeves has now said that she "wasn't aware that previous Chancellors had released their tax return" after yesterday's row over making her HMRC filings public.
She told Times Radio this morning: "I'm very happy to release my tax return in accordance with what's happened in the recent past, and I'll be doing that alongside the Prime Minister in due course."
When probed on whether Kemi Badenoch should follow suit, the Chancellor said: "That's a matter for Kemi Badenoch, but the Prime Minister and I will be releasing ours."
Our top story from yesterday: Reeves WILL publish tax return but Badenoch refuses after GB News question forces Chancellor U-turn
Rachel Reeves has performed a spectacular U-turn just hours after refusing to release her tax return with the public.
The Chancellor had ruled out sharing the details after being quizzed by GB News' Political Editor Christopher Hope at her growth speech in Oxfordshire earlier today.
He asked: "Millions are sending in their tax returns this week to HMRC, you're in charge of it, will you publish your tax return?"
But Reeves quashed his question, saying: "Chancellors and Prime Ministers haven't published their tax returns in the past, and I don't have any plans to do so."
However, a Treasury spokesman has since confirmed the details will soon be made public.
Reeves's decision to U-turn on her tax return comes shortly after it was pointed out that ex-PM Rishi Sunak and former Chancellor Jeremy Hunt both shared information on their tax affairs while holding high office.
But in the face of Reeves eventually opting to release her tax return, Tory leader Kemi Badenoch refused to make the same promise.
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