Lyon president Jean-Michel Aulas has confirmed Alexandre Lacazette's move to Arsenal should be completed "within the next day or two".
Arsenal's opening bid of £39m was turned down last month, but significant progress has been made in talks between the clubs.
Aulas confirmed the deal is worth up to £43.8m (€50m), meaning it would eclipse the club-record £42.5m Arsenal paid for Mesut Ozil four years ago.
Aulas told French outlet Le Progres: "Alexandre Lacazette's transfer to Arsenal could be actioned within the next day or two.
"The figure reported by the English media of around €67m (including €12m in add-ons) is impossible and not realistic. Arsenal's first offer was around €45m, the transfer will be concluded in the range of €45m to €50m.
"It constitutes, without doubt, a record transfer fee for Arsenal, [sic] and for Lyon of course!"
Last month, Lacazette said he would only move to a club who are playing in Europe's premier club competition but it appears the 26-year-old's stance on the matter has softened.
Lacazette had verbally agreed to join Atletico Madrid this summer but the move fell through after the Court of Arbitration for Sport confirmed on June 1 that Atletico would be banned from registering players during this window.
The free-scoring striker netted 37 times in 45 games last season and has two years left on his existing Lyon deal.
Lacazette boasted the highest chance conversion rate in Europe's top five leagues last season (38.9 per cent). His record of 28 league goals last term was more than the combined tally of Arsenal quartet Olivier Giroud, Theo Walcott, Danny Welbeck and Lucas Perez.