US president Donald Trump has extended an invitation to his Russian counterpart Vladimir Putin to visit Washington in the autumn.
It follows their meeting in Helsinki on Monday which is still making headlines.
Mr Trump received widespread criticism for saying at a joint-press conference on Monday that Russia did not interfere in the 2016 US presidential election. He backtracked a day later - confusing the public and media alike.
Moscow has said they are "open" to discussing a possible visit by Mr Putin to Washington, Russia's ambassador to the US said on Friday.
Is this unprecedented?
No, several Russian leaders have been invited to Washington - even at the height of the Soviet Union.
- Nikita Khrushchev
In 1959, Dwight Eisenhower met with Nikita Khrushchev - though hopes for a fruitful relationship were dashed after the Soviets shot down an American U-2 spy plane over Russia.
The events were dramatised in the blockbuster film Bridge of Spies.
- Mikhail Gorbachev
In 1987, Mikhail Gorbachev met Ronald Reagan, hailed as one of the most famous encounters, the pair signed the Intermediate-range Nuclear Forces Treaty.
- Boris Yeltsin
In 1994, Boris Yeltsin met Bill Clinton for the first time at the White House as the United States tried to forge better relations. Perhaps leaving the biggest impression, Yeltsin was reportedly found drunk, roaming the streets in his underwear trying to hail a cab to go out for pizza.
- Vladimir Putin
Mr Putin has already been invited to Washington by a US president. In 2001, he was entertained by George Bush in Washington and Texas.
17 years later - despite the controversy surrounding election meddling - could he make another trip to the White House?
The latest on Donald Trump and Vladimir Putin's proposed meeting from ITV News Correspondent Juliet Bremner: