BORIS Johnson has used his speech at the Conservative Party conference to praise Theresa May and insist the Cabinet is entirely united behind her approach to Brexit.

The Foreign Secretary, whose own “red lines” on Brexit have overshadowed the conference and led to calls for May to sack him from her Cabinet, paid tribute to the Prime Minister.

Responding to the General Election – in which the Tories lost their majority – Johnson stressed that Labour under Jeremy Corbyn did not win. He told the conference in Manchester: “You won – we won. Theresa May won.

“She won more votes than any party leader and took this party to its highest share of the vote in any election in the last 25 years – and the whole country owes her a debt for her steadfastness in taking Britain forward as she will to a great Brexit deal.

“Based on that Florence speech on whose every syllable, I can tell you the whole Cabinet is united.”

Johnson used his speech to attack Corbyn as “that Nato-bashing, Trident-scrapping, would-be abolisher of the British army” and what he called the “zombie” ideology of socialism.

In comments which will bolster speculation about his leadership ambitions, he also strayed beyond his foreign affairs brief, though was at pains to point out the actions already being taken by May’s Cabinet.

Setting out the battle against Labour, Johnson told the conference: “We may have the most illustrious battle honours of any political party but now we have to win the battle for the future and the way to win the future is not to attack the market economy, not to junk our gains but to make it work better – make it work better for the low paid – turning the living wage under this Conservative Government into a national living wage.

“Make it work for all those who worry their kids will never find a home to own – building hundreds of thousands of homes.

“Make it work better for parents who can’t find good enough childcare – with 30 hours free care for three and four-year olds.

“And above all help people who are struggling, by driving benefit reforms that have helped millions back into the dignity and self-esteem that goes with having a job and which has seen inequality fall – as the Chancellor pointed out yesterday – to the lowest levels for three decades.”

The Foreign Secretary said it was time for the “lion” – the British people – to be allowed to “roar” after Brexit. “We can win the future because we are the party that believes in this country and we believe in the potential of the British people....We are not the lion. We do not claim to be the lion. That role is played by the people of this country.

But it is up to us now – in the traditional non-threatening, genial and self-deprecating way of the British – to let that lion roar.”

Johnson called Corbyn was a “superannuated space cadet from Islington” and suggested he should be sent “into orbit”.

But speaking earlier in the European Parliament in Strasbourg, Manfred Weber, head of the European People’s Party, the largest political group in the parliament, called for Johnson to be sacked.

He said Johnson’s recent articles show “the British Government is trapped by their own party quarrels and political contradictions.”

“We need a clear answer who is responsible for the British position [on Brexit],” Weber said.

“Is it Theresa May, Boris Johnson, or even [Brexit Secretary] David Davis?”