Chelsea have reached an agreement to sign striker Diego Costa from Atletico Madrid, the Premier League club have announced.

The Spain international had long been linked with a move to Stamford Bridge and now the Blues have confirmed they have met the buy-out clause for the 25-year-old, believed to be €40 million.

“Chelsea Football Club can confirm an agreement has been reached with Atletico Madrid for the transfer of Diego Costa, with Chelsea meeting the buy-out clause for the Spanish international,” read a statement on the club’s official website.

Brazil-born Costa netted some 35 goals for Atletico last season as they won the Spanish title and reached the Champions League final, where they lost in extra-time to Real Madrid.

The 25-year-old emerged as the leading summer transfer target for Blues manager Jose Mourinho, who was determined to add some firepower to a squad which came up just short behind Manchester City and Liverpool in the Premier League and were knocked out of Europe in the semi-finals by Atletico.

Defender Ashley Cole has left Chelsea this summer at the end of his contract, along with England midfielder Frank Lampard.

However, former Arsenal captain Cesc Fabregas was signed from Barcelona on June 12th, the day before Spain crashed to a 5-1 defeat to the Netherlands in their opening World Cup match in Brazil.

Earlier on Tuesday, Chelsea announced goalkeeper Mark Schwarzer had signed a new one-year contract.

The former Australia international, 41, headed to Stamford Bridge last summer on a free transfer from west London neighbours Fulham to offer back-up to Petr Cech and went on to make 12 appearances – including the semi-final against Atletico after injury to the Chelsea number one.