London, England (CNN) -- David Cameron, Britain's youngest prime minister for almost two centuries, began his first day at Downing Street by appointing Cabinet ministers from his own Conservative party and coalition partners, the Liberal Democrats.
At a news conference in the garden of 10 Downing Street on Wednesday afternoon, Cameron said the new coalition government was "a five-year government." With Liberal Democrat leader Nick Clegg -- who was named deputy prime minister -- standing at his side, Cameron assured the public that new elections would not need to be called soon.
The names of several Cabinet ministers were confirmed by their respective departments, including William Hague as foreign secretary; George Osborne as chancellor of the exchequer, which is equivalent to treasury secretary; and Liam Fox as defense secretary. All are from the Conservative Party.
Other Conservative appointments included Theresa May as home secretary, Kenneth Clarke as justice secretary, Andrew Lansley as health secretary, and Michael Gove as education secretary, Downing Street said.
In addition to Clegg as deputy prime minister, four other Liberal Democrats will also be named to Cabinet posts, Downing Street and the party said.
Downing Street named two of them as Vince Cable, who is now the business secretary, and David Laws, who was made the chief secretary to the treasury.
The decision by Cameron and Clegg to enter a coalition capped five days of uncertainty that followed last Thursday's election, in which no party received a majority.
Days of negotiations between the Conservatives, the Liberal Democrats, and the Labour Party of former Prime Minister Gordon Brown resulted in the announcement of a coalition between the Conservatives and Lib Dems.
"I'm absolutely delighted that we do have a new government," Gove told CNN on Wednesday.
"I think the really important thing is that the policies that we were arguing for during the course of the election, and the policies of the Liberal Democrats, have now been brought together on a platform which will give the country exactly the type of government that it needs at this time -- strong and stable."
Cable, of the Liberal Democrats, said he realized the challenges of working with Osborne, of the Conservatives, in his new role. Financial analyst David Buik of London-based BGC Partners said he was "skeptical" of the pairing, however.
"What concerns me is the missing chemistry, the possible missing chemistry, that may be from the Conservative Party and the Liberal Democrats, particularly in areas such as finance," Buik told CNN. "The Conservatives were very keen to deal with the budget deficit PDQ, and Vince Cable was adamant until a few weeks ago in waiting until the new year."
At the Foreign Office, the new national security council planned to meet Wednesday. Cameron established the council to oversee all aspects of Britain's security, and appointed longtime civil servant Peter Ricketts to be his national security advisor, the Foreign Office said.
Cameron will chair the council, whose members will include several top cabinet members. Its inaugural meeting Wednesday afternoon was focusing on Pakistan and Afghanistan, the Foreign Office said.
"It is our most urgent priority here in my work to make sure we've got a grip on what is going on in Afghanistan," Hague told Sky News. "We will never forget that our troops are out there. We've been fighting some political battles here, but they are in a real battle out there."
Hague also vowed to protect the "special relationship" between Britain and the United States, keeping it "solid but not slavish." The United States is an "indispensable partner" of Great Britain, Hague said.
Queen Elizabeth II named Cameron prime minister Tuesday night, shortly after Brown resigned.
Brown had said Monday he would step down as leader of his party by the fall, but he changed course Tuesday, announcing he was quitting his party post immediately.
His deputy, Harriet Harman, will lead the Labour Party until a leadership contest can be held, he told party activists.
His party came in second, behind the Conservatives, in parliamentary elections last week, but no party won an absolute majority.
Cameron, 43, becomes the country's first Conservative prime minister since the Labour Party, under Tony Blair, defeated John Major in 1997, and is the youngest for almost two centuries.
Coalition governments are extremely rare in British politics. The last time there was a "hung parliament" with no party holding a majority of the seats in the House of Commons was 1974. Coalition talks then between the Conservatives and Liberals failed, and a short-lived minority Labour government took power.
But Cameron said Tuesday a coalition government was "the right way to provide this country with the strong, the stable, the good and decent government that I believe we need so badly."
The two parties would command a clear majority in the 650-seat House of Commons, but have a number of key policy differences.
Cameron is Queen Elizabeth II's 12th prime minister -- including Harold Wilson twice, for his two non-consecutive terms -- since she was crowned in 1952.