Ben White is expected to undergo his Arsenal medical on Wednesday, ahead of his £50m move from Brighton.
The two Premier League sides reached an agreement on the transfer fee.
However, White has been on holiday and will return this week to finalize the switch.
The Gunners had a £40m bid for the England centre-back rejected, while an improved offer of £47m was also knocked back.
Brighton have also inserted a sell-on clause for White, who featured in all but two of league fixtures last season as they finished 16th.
EPL: Arsenal agree £50m deal for White
The 23-year-old was then included in the Three Lions’ Euro 2020 campaign and played in the two warm-up games against Austria and Romania before the tournament.
White would become Mikel Arteta’s third summer signing, following the arrivals of left-back Nuno Tavares from Benfica and midfielder Albert Sombi Lokonga from Anderlecht.
