Chelsea have agreed a deal worth up to £40m to sign Atalanta defender Honest Ahanor.

The 18-year-old Italian has permission to complete a medical in London and has agreed personal terms.

Chelsea first expressed an interest in the defender when they signed right-back Marco Palestra from the Serie A side in July.

It remains unclear whether Chelsea plan to involve the teenager in new manager Xabi Alonso's squad and his representatives say he could immediately move on loan to another Premier League club.

Ahanor, who mainly plays at left-back, joined Atalanta from Genoa on a three-year deal last summer for a reported fee of 16m euros, plus 4m euros in add-ons.

He made 28 appearances in Serie A for Atalanta last season, establishing himself as a regular starter. He also made his Champions League debut in a 2-1 win against Club Brugge in September.

In May, he was called up by Italy for friendly matches against Luxembourg and Greece.

Chelsea boss Alonso has been building his squad since taking over at Stamford Bridge in July, signing England midfielder Morgan Rogers from Aston Villa for a club record £117m, and adding experienced Premier League players Danny Welbeck and Jordan Henderson.

Chelsea face Brighton at home in the Premier league on Sunday after beating Fulham 3-2 in their opening match of the season on Monday.