The minister in charge of the UK's Ukrainian refugee scheme has quit the government before a new party leader takes over as prime minister.
The Tory peer and former Watford MP said his work was "essentially complete" and the position was always meant to be temporary.
In government since March, Lord Harrington stressed his resignation is no reflection on either Liz Truss or Rishi Sunak - the two candidates vying to succeed Boris Johnson as PM next week.
Thanking Mr Johnson for appointing him, he said his decision means the next prime minister can “save” on a ministerial position.
The former Conservative MP said he had spoken to both Number 10 and the Tory leadership candidates before publicly confirming his decision.
“We now have the permanent machinery in place to deal with human misery coming to this country from wherever they come from without the need for a designated minister to be in charge,” he said.
“With monthly reports for the Secretary of State, whoever he or she may be, there should now be a permanent delivery mechanism.
“Never again will we have people arrive in the UK and go into hotels without a plan, as happened with those coming from Afghanistan and from the Ukraine, where at the beginning we didn’t have any idea where to put them all.”
Lord Harrington has reportedly called on the next PM to double payments to families hosting Ukrainian refugees after six months to £700 a month.
He has said he will take on a voluntary role helping refugees after he leaves government.
“I was brought in to do a very specific job, which was to set up working machinery across government to deal with helping the Ukrainians in need,” Lord Harrington continued.
“I believe we now have a process and procedure in place that means there won’t necessarily be the need for a minister like myself.
“I’m not walking out on the role or either candidate and will continue to support where helpful.
"But what I was specifically asked to do is essentially complete so it seems right that I make clear to both leadership contenders that they may be able to save on a ministerial post when they take over.
“Or at least have the option to shape the role for the next phase with a new person now I’ve established a successful system.”
Mr Johnson was among those to pay tribute to his efforts, with the outgoing Prime Minister saying that government would miss his “wealth of experience”.
More than 100,000 Ukrainians have arrived in the UK since the invasion began - but some families have struggled with the cost of hosting, with many quitting the scheme after six months or less.
The government launched two visa schemes in March so those fleeing the conflict in Ukraine could come to the UK for up to three years. The family scheme allows Ukrainian nationals and their relatives to join other family already living in the UK, while Homes for Ukraine allows Ukrainian nationals and their relatives to come to the UK if they have a sponsor who can provide accommodation.
Hundreds of arrangements with family members or hosts, however, have broken down, or accommodation has been unsuitable or unavailable.
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