Boris Johnson has spoken to US President Donald Trump ahead of meeting him for the first time since becoming prime minister on Sunday.
The leaders, who will meet at the G7 summit in France, discussed “foreign policy issues and global trade”.
No 10 said they “looked forward to speaking further” at the summit.
Mr Trump has praised Mr Johnson, calling him “Britain Trump”, and predicted a speedy US-UK trade deal after Brexit.
Mr Johnson intends to make clear his red lines for a deal when he meets Mr Trump, taking the NHS “off the table” in negotiations, the Daily Telegraph reported.
A UK government spokesman said: “Of course we want to move quickly, but we want to get the right deal that works for both sides.”
The PM will also meet European Council President Donald Tusk.
Mr Johnson has had a hectic week of diplomacy, visiting Paris and Berlin in an effort to persuade the EU to amend the withdrawal agreement it reached with his predecessor Theresa May.
- Trump: US and UK working on ‘very substantial’ deal
- Johnson: New Brexit deal won’t be a cinch
- Trump-Johnson relationship ‘will be sensational’
- Backstop indispensable, Macron tells Johnson
The G7 summit in Biarritz – a get together of most of the leaders of the world’s largest economies – comes with just over two months until the Brexit deadline of 31 October.
Mr Johnson says the UK will leave the EU by then, whether or not the government reaches a deal to replace Mrs May’s deal – which was rejected by Parliament.
He wants to renegotiate the backstop – part of the agreement which aims to prevent a hard border on the island of Ireland after Brexit – but the EU has ruled this out.
Earlier this week, German Chancellor Angela Merkel said the onus was on the UK to find a workable alternative plan.
Mr Johnson will meet Mr Trump for one-on-one talks on the sidelines of the summit on Sunday morning, and hold a separate meeting with Mr Tusk later.
In July, Mr Trump said talks about a “very substantial” post-Brexit trade deal between his country and the UK were under way.
He also said he believed Mr Johnson would do “a great job” as prime minister, adding: “He’s a different kind of guy, but they say I’m a different kind of guy too.”
The president said Mr Johnson would “straighten” out Brexit negotiations.
In 2015, while Mayor of London, Mr Johnson accused Mr Trump of “stupefying ignorance” for calling parts of the city no-go areas.
But he later said the US president had “many, many good qualities”.
In July, after Mr Trump used Twitter to criticise then-Prime Minister Theresa May and her handling of Brexit, Mr Johnson said Mr Trump “could perhaps be more diplomatic” in his tweets.
The G7 summit runs from Saturday to Monday.
On Friday, French President Emmanuel Macron – who is hosting the summit – and German Chancellor Ms Merkel said the ongoing fires in Brazil’s Amazon rainforest must be discussed among the G7 leaders this weekend.
On Friday, Mr Johnson said reaching a new deal with the EU would not be “a cinch”, but reported “new mood music” from French President Emmanuel Macron and German President Angela Merkel”.
Speaking during a visit to Devon, the prime minister said the government was “making progress”, but would “have to prepare to come out without an agreement”.
Boris Johnson and Donald Trump speak ahead of G7 meeting}