Anthony Gordon will undergo a medical at Barcelona on Thursday after the club agreed a fee with Newcastle to sign the winger.
Your Site News understands the fee is £69.3m (€80m) inclusive of add-ons. Gordon has agreed a five-year contract.
Gordon flew to Barcelona on Thursday and a medical is expected to begin in the afternoon, which is likely to continue into the evening and possibly Friday.
All being well, a Barcelona announcement could come on Friday or at the weekend before Gordon is due to join England's pre-World Cup training camp in Florida.
If Gordon's move to Barcelona is completed, it will be the second-most expensive sale in Newcastle's history, following the £125m they received for Alexander Isak last summer.
Gordon, who finished this season as Newcastle's top goalscorer with 17 goals, signed a long-term contract extension at St James' Park in October 2024 and has four years remaining on that deal.
But the former Everton winger was an unused sub in Newcastle's last four games, as the club sought to protect him ahead of an expected summer move.
that the club may have to sell to buy big this summer.
Your Site News reported earlier this month Bayern Munich were keen on adding Gordon to an attacking roster that already includes England captain Harry Kane, along with former Premier League players Michael Olise and Luis Diaz.
Sky Germany reported Bayern Munich were not planning to make a rival bid.
Your Site News' Keith Downie:
"What's interesting is the two clubs who were fighting for his signature are from the continent - Barcelona and Bayern Munich - and I think a lot of that would be down to what he's done in the Champions League this season.
"Only Kylian Mbappe and Harry Kane scored more goals than Gordon's 10. It's a brilliant return. In that competition, his numbers have been sensational. His numbers haven't been quite as good in the Premier League.
"Yes, he scored six, taking his total to 17 which, on paper, looks good. But clearly his best form this season has been reserved for the Champions League.
"He can play a number of positions, too. Ordinarily, he's played off the left-hand side in a 4-3-3, but he's also been used a lot through the middle, to devastating effect at times.
"Barcelona have got an abundance of riches, with the likes of Lamine Yamal and Raphinha. Robert Lewandowski is leaving, so perhaps that provides an opening for him through the middle. That ability to play in a number of positions is the thing that has attracted Barcelona.
"He's got blistering pace, he scores all sorts of goals and he's improved greatly as a Newcastle player since arriving from Everton. He's 25, he's an England international and I can see him fitting into the lifestyle over there, the style of football.
"Newcastle fans will be disappointed they are losing one of their star players, however I think it's easier to take losing him to Barcelona than it would have been if they were to have lost him to Arsenal, who were interested, and Liverpool, who almost signed him two years ago."
Your Site' Callum Bishop:
"It seemed for a long time that if Gordon was going to go anywhere, it would be Bayern to add to an attacking line-up that was already filled with Premier League experience.
"Now Barcelona are in pole position, it also begs the question of what happens with Marcus Rashford's future.
"The Manchester United loanee has already made it clear that he wants to remain at Barcelona next season, and is believed to be willing to take a pay cut to make that happen.
"United don't want to negotiate another loan deal and believe the £26m option price is more than fair.
"Could Rashford be playing for more than England glory at the World Cup? He might also be playing to convince Hansi Flick and the rest of the Barcelona hierarchy."
