According to The Athletic, the 28-year-old has informed Newcastle of his desire to join the Premier League champions, who are looking to add a marquee midfielder to partner Declan Rice.
Arsenal had an initial approach worth around £55m rejected last month. ESPN reports the Gunners are now willing to go to around £60m, though Newcastle value their captain at closer to £100m and have so far refused to sanction a sale.
It is a blow for Eddie Howe, who has already seen Sandro Tonali join Tottenham for an initial £92.5m, while Anthony Gordon left for Barcelona in a £69.3m deal. Guimaraes is understood to be increasingly frustrated by the lack of Champions League football following those departures, as well as Isak's exit to Liverpool last summer.
Since arriving from Lyon in January 2022, Guimaraes has made 153 Premier League appearances for Newcastle United, scoring 30 goals and setting up 26 more. He was part of the side that won the Carabao Cup in 2025, ending the club's long wait for a major trophy, after which he spoke emotionally of wanting fans to one day sing his name "the way they do to Alan Shearer."
The Brazilian, who still has two years left on his contract, endured a difficult World Cup, missing a penalty as Brazil crashed out in the last 16 to Norway.
Arsenal have yet to hold direct talks with Newcastle, though Real Madrid, Manchester City and Barcelona are also said to be monitoring the situation as the transfer saga develops.
Guimaraes' arrival would intensify competition for places in Mikel Arteta's midfield, with Martin Zubimendi's status as a regular starter potentially under threat. Arteta is said to prize the Brazilian's leadership and Premier League experience highly enough to make him the club's priority midfield target this summer.
For Newcastle, losing their captain would represent a third major departure of the window and revive memories of last year's protracted Isak saga, which also ended in an unwanted sale to a direct rival. Howe's side are said to be exploring a new contract for Guimaraes as they attempt to head off Arsenal's interest.