Presidents Obama and Medvedev pop out for burger

US President Barack Obama and Russian President Dmitry Medvedev have taken a break from bilateral meetings at the White House to travel outside Washington DC for a quick, informal lunch.

Traveling by motorcade, the two leaders headed for Ray's Hell Burger in Arlington, Virginia, a popular spot where Obama ate last year with Vice President Joe Biden.

A cheer went up from customers when the presidents walked in, but the lunch crowd largely left the presidents alone. During their meal, Obama and Medvedev sat at a table with their interpreters, sharing a conversation through them.

The US president had a cheeseburger with cheddar cheese, onion, lettuce, tomato and pickles, whilst his Russian guest had a cheeseburger with cheddar, onion, jalapenos and mushrooms.

Obama drank iced tea and Medvedev sipped a Coke, while the presidents, both in shirt sleeves on a hot summer day, shared a portion of fries.

Later in the day, and back to official business, the two leaders held a joint news conference at the East Room in the White House.

Obama declared that he and Medvedev had "succeeded in resetting" the relationship between the former Cold War adversaries that had dipped to dangerously low levels in recent years.

He directly acknowledged differences in some areas, such as Moscow's tensions with neighbouring Georgia, but said "we addressed those differences candidly."

Obama also announced that the US and Russia had agreed to expand cooperation on intelligence and the counterterror fight and worked on strengthening economic ties between the nations.

The US leader gave Russia perhaps the biggest gift it could have wanted from the meetings: an unqualified, hearty plug for Moscow's ascension to the World Trade Organisation. Russia has long wanted membership but US support in the past has come with conditions.