Cameron US tour: PM and Obama consider oil release
David Cameron has said he and and Barack Obama discussed the possibility of releasing emergency oil reserves during talks in Washington.
No final decision was taken, but BBC political editor Nick Robinson said it was a sign of the president's concern at the high level of US fuel prices.
The UK has previously released oil from its reserves as part of co-ordinated efforts to dampen soaring prices.
Mr Cameron also laid flowers at Ground Zero in New York.
He was shown round the 9/11 memorial with his wife Samantha - who was in the city on the day of the attacks - by New York mayor Michael Bloomberg.
They also met the families of British victims of the 2001 attacks in New York.
Mr Cameron told the BBC it was a good place to remember why the action in Afghanistan was necessary.
"Here at the site of the Twin Towers, Ground Zero, here is the place to remember why what we do overseas is so important, so people are safe at home," he said.
He insisted there would be a handover to a capable Afghan government by the end of 2014 whether or not there was a political settlement involving the Taliban, who have pulled out of talks.
The UK's PM also said that the two men had discussed releasing the strategic oil reserves because "we are all facing the problem of higher oil prices".
Although they had not reached a decision he said they both wanted to "do what we can to help" families facing economic tough times.
Mr Cameron's itinerary for the third day of the visit included engagements at New York University, City Hall and a charter school - seen as the model for the free schools being introduced in the UK.
He also met the mayor of Newark, New Jersey, Cory Booker, to hear about efforts he has made to turn around the city after years of decline.
Mr Cameron told Mayor Booker he "hugely admired" his work and thought the UK could learn from his initiatives on police accountability, education, reducing reoffending and urban regeneration.
"I'm a great believer big city leaders can do great things for their communities," the prime minister said.
He also held his first "Cameron Direct" event outside the UK, at New York University, where he was asked about the NHS, the Falklands and the Olympics.
Nick Robinson said some close to the prime minister have pointed to the possibility of an oil release as one of the things Mr Cameron can do to be helpful to President Obama.
Both the PM and the president are known to be extremely concerned that instability in the Middle East and talk of a war between Israel and Iran could drive up oil prices even further, with serious consequences for global economic recovery.
On Wednesday, the leaders spent time discussing issues such as Syria, Iran, Yemen and the war in Afghanistan.
Speaking at a press conference afterwards, Mr Cameron said the mission in Afghanistan was moving into its "final phases".
Both leaders stressed that progress had been made in the country - despite the loss of US, British and Afghan lives.
Mr Obama confirmed international forces would take on a support role from 2013, with Afghans in full charge of security in 2014.
The UK prime minister also raised the issue of reviewing how extradition agreements were operating amid concerns US officials were having to produce less evidence than their British counterparts to support cases.
But at the state dinner the leaders returned to what has been a frequent theme during the visit - their countries' close relations - and spoke of their personal bond.
Mr Cameron praised the president for having "pressed the reset button on the moral authority of the entire free world".
Comparing Mr Obama to former US President Theodore Roosevelt, Mr Cameron said he understood that "America must do the right thing but to provide moral leadership America must do it in the right way too".
He praised Mr Obama for being strong when required to defend US national interests, while not rushing to "pick fights", and for having "found a new voice for America with the Arab people".
"Barack, it is an honour to call you an ally, a partner and a friend," he added.
Likewise, Mr Obama said of the prime minister that he was "the kind of partner you want at your side".
"I trust him. He says what he does and he does what he says. I've seen his character. I've seen his commitment to human dignity during Libya."
The president also spoke of Mr Cameron and his wife Samantha having "shown a measure of strength that few of us will ever know", in a reference to the death of their eldest son, Ivan, at the age of six.
The 360 guests at the star-studded dinner enjoyed bison Wellington, combining the classic British pastry-around-meat dish with North Dakota buffalo loin.
Several of those in attendance were said to be key donors to President Obama's re-election fund, such as movie mogul Harvey Weinstein.
Other notable guests included actor George Clooney, golfer Rory McIlroy and Homeland star Damian Lewis.
Hugh Bonneville and Elizabeth McGovern, from ITV period drama Downton Abbey, British Olympic heptathlon gold medallist Denise Lewis, and Virgin boss Sir Richard Branson also attended.
Entertainment was provided by US R&B star John Legend and English folk-rock band Mumford & Sons - a favourite of Mrs Cameron.