The 59-year-old will be the second woman to lead Britain, following in the footsteps of fellow Conservative, "Iron Lady" Margaret Thatcher. She promised to lead a "one-nation" government dedicated to social justice and making "Britain a country that works for everyone".
"The number one challenge is to stabilize the economy, send signals of confidence about the future, the plans we have for the future, to the markets, to businesses, to worldwide investors", Hammond told Sky News.
Schulz said the cabinet, like the one run by May's predecessor David Cameron, is based on solving internal splits in the ruling centre-right Conservative Party rather than promoting the national interest.
On a more serious note, Cameron said that he cared passionately about the United Kingdom, but added that "we need to make sure as we leave the European Union, how we keep the benefits of the common travel area".
Watched from the public gallery by wife Samantha and children Nancy, Elwen and Florence, Mr Cameron paid tribute to the support he had received from his family, telling MPs: "The pressure often bears hardest on those around us in this job".
He wished his successor Theresa May luck in her negotiations to have Britain leave the European Union - the matter that caused his demise.
Later, Queen accepted Cameron's resignation.
David Cameron said he was proud his government had put 173,000 more people into work in the West Midlands, in his final day as Prime Minister.
Theresa May officially became Britain's prime minister after meeting with Queen Elizabeth II on Wednesday.
Germany's Angela Merkel also spoke by phone with May to congratulate her on the appointment, the chancellor's spokesman said.
During the 30-minute session, Cameron revealed he had answered more than 5,500 at PMQs during his six year tenure, and displayed some of his customary wit at the despatch box.
Mr Cameron also insisted he loved the Number 10 cat, Larry - following newspaper reports that he wasn't fond of the feline - and even held up a photograph showing Larry sitting in his lap.
Cameron's audience with the Queen will be swiftly followed by the arrival at the Palace of May, who will be formally appointed the UK's second female Prime Minister by "kissing hands" with the monarch.
De Maiziere has been outgoing Home Secretary May's German counterpart for several years as his country's top security official.
David Cameron will continue in his role for MP for Witney.
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Boris Johnson, probably the best-known member of the new cabinet in the US, is now Britain's foreign secretary, making him the country's senior diplomat as Britain extricates itself from the EU. "The Channel will not get any wider once we leave the European Union, and that is the relationship we should seek".