“If ‘Global Britain’ is going to achieve its full and massive potential then we must bring Dfid to the FCO,” Mr Johnson said earlier this year.
He also accused the department of “inevitable waste as money is shoved out of the door in order to meet the 0.7 per cent target” – raising fears its budget will be slashed.
At her final prime minister’s questions, Ms May ducked an invitation to give “hard advice” to Mr Johnson, but did back a Tory MP’s call for a “self-standing” Dfid to survive.
“I am proud of the fact that we have a department of international development,” she told the House of Commons.
Noting that a Conservative-led government had legislated for the 0.7 per cent target,” Ms May added: “It is an important element of global Britain – and an important element of our standing in the world.”
In stark contrast, Mr Johnson told The Financial Times, in February: “We can’t keep spending huge sums of British taxpayers’ money as though we were some independent Scandinavian NGO [non-governmental organisation].
He added: “It is perfectly possible to boost global development in a way that coheres much better with UK political and indeed commercial objectives.”
The report Mr Johnson was seen as paving the way for the £13.4bn pot to fund all peacekeeping work and world service broadcasting – diverting much of its cash to the Ministry of Defence and the BBC.
It was strongly criticised by aid campaigners, with Save The Children warning the UK was in danger of losing “its status as an international development superpower”.
The comments came at a feisty final question time, at the end of which Conservative and most Liberal Democrat MPs – but not Labour’s – gave Ms May a standing ovation.
The outgoing prime minister fought back tears, having earlier told Jeremy Corbyn to consider whether his time as leader is also up.
She taunted the Labour leader, saying “It's very good to see the Conservative Party in good heart, which is more than I can say for the Labour Party.”
A number of Labour MPs criticised Conservatives cheering for the leader they had forced out of the door, describing it as “hypocritical”.
“Amazing how many Tory MPs are cheering her on when only a few weeks ago they were stabbing her in the back,” tweeted MP Luke Pollard, “that's politics I guess.”
And Diane Abbott, the shadow home secretary, tweeted: “Hypocritical Tory MPs cheering their outgoing leader.”
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