Arsenal have completed the transfer of Alexis Sanchez from Barcelona for a fee believed to be in the region of £30m.
Sanchez, 25, has signed a long term contract at the Emirates in a move that could also pave the way for Liverpool striker Luis Suarez to complete his move to the Nou Camp.
"I'm so happy to be joining Arsenal, a club which has a great manager, a fantastic squad of players, huge support around the world and a great stadium in London," Sanchez told the club's official website.
"I'm looking forward to meeting my new team-mates and to be playing for Arsenal in the Premier League and Champions League. I will give my best to Arsenal and want to make all the supporters happy."
Arsene Wenger added: "As many people have seen during the World Cup this summer, Alexis is a fantastic footballer and we are delighted that he is joining us at Arsenal Football Club."Alexis will add power, creativity and much quality to our squad and we are all looking forward to him joining up with us in a few weeks.
"He has consistently produced top-quality performances at the highest level for a number of seasons now and we are all excited to see him integrate into the Arsenal squad. I'm sure all Arsenal supporters will join me in welcoming Alexis to our club."
Liverpool had been keen to bring Chile international Sanchez to Anfield as part of the Suarez deal but the club conceded defeat upon learning of his desire to join the Gunners. Juventus were also eager to bring the player back to Serie A but he has instead opted for a move to London.
Sanchez was an integral member of the Chile side that shone in the World Cup before they were halted by Brazil in the quarter-finals on a penalty shootout, scoring twice for Jorge Sampaol's impressive side.
The new Arsenal recruit is likely to become the club's highest earner alongside record signing Mesut Ozil, collecting a wage of £140,000 a week, according to Chilean newspaper La Tercera.
The Gunners are also expected to confirm the signing of Newcastle United full back Mathieu Debuchy in the coming days having reportedly undergone a medical at the club's London Colney training ground ahead of an £11m switch.