Former education secretary Damian Hinds has been appointed as security minister, Downing Street said.
The announcement on Friday came hours after the Home Office said Home Secretary Priti Patel had expanded her brief to take on the responsibilities of the security minister following criticism of the Government for failing to replace James Brokenshire.
Labour said it was a “humiliating U-turn” by the Government.
East Hampshire MP Mr Hinds was education secretary from January 2018 to July 2019.
Ms Patel said on Friday she is “fully sighted and fully aware of everything that goes on” on security issues.
The Government has been criticised in recent days after failing to replace Mr Brokenshire as security minister, with the UK rocked by both a gunman’s killing spree and the arrest of a British national in Germany on suspicion of spying for Russia.
But Ms Patel has denied that a lack of a replacement for Mr Brokenshire, who stepped down on July 7 for health reasons, had made it more difficult for the Government to keep a grasp on potential threats, such as the online activity of the man behind the shootings in Plymouth, Devon, on Thursday.
Asked whether the failure to appoint a new security minister had hindered the Government’s ability to respond to such events, Ms Patel said: “I would say that that is absolutely not the case.
“I am the Home Secretary and I oversee these security issues, and I have been doing that throughout.
“I’ve been kept fully updated and on all issues, all incidences, including those types of issues and incidences that don’t even reach the public awareness and consciousness.
“I’m fully sighted and fully aware of everything that goes on.”
A Home Office spokesman confirmed the Home Secretary’s remit included “those related to national security” in the wake of Mr Brokenshire’s resignation, following reports suggesting she would absorb the role permanently into her own.
For Labour, shadow home office minister Conor McGinn, said: “This is another humiliating U-turn from the Conservative Government.
“I welcome the fact the Prime Minister has belatedly listened to sense and finally appointed a new Security Minister. But there is no getting away from the fact that the Home Office is lurching from crisis to crisis and chaos reigns across Government.”
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