Arsenal are set to sign Porto going after midfielder Fabio Vieira in a deal worth up to €40 million, sources have told.

The 22-year-old is expected to have a medical in London on Friday and will pay an initial €35m with a further €5m possible in performance-related add-ons.

Albeit the better subtleties are yet to be closed, sources claim Arsenal will pay an initial €35m with a further €5m conceivable in performance-related add-ons.

Vieira has scored seven goals and registered 16 assists in 39 appearances for Porto and has played in various positions, including as a No. 10, a No. 8 and a second striker.

He is yet to make a senior international appearance for Portugal but has featured 20 times for their Under-21s.

Vieira had a release clause of €50m however sources have affirmed Porto acknowledged a lower offer from Arsenal and excepting any last-minute issues, the deal is expected to be finished in the coming days.