LONDON, May 8 (Xinhua) -- Chelsea will appeal against a FIFA transfer ban which prohibits them from signing players this summer or in January 2020 to the Court of Arbitration for Sport (CAS).

The club confirmed the news on Wednesday after FIFA rejected their appeal against the ban, which was imposed in February following an investigation into the irregular signing of foreign players for their youth system.

Chelsea maintain they have not committed any irregularities and published a communique explaining why they will appeal to CAS.

"Chelsea FC has today received the decision of the FIFA Appeal Committee ... The club is very disappointed that the transfer ban of two consecutive registration periods was not overturned."

"Chelsea FC categorically refutes the findings of the FIFA Appeal Committee. It acted in accordance with the relevant regulations and will appeal the decision to the Court of Arbitration for Sport (CAS)," insists the club.

Current rules state no players younger than 18 can join a club from another country unless their parents are moving to that country for non-footballing reasons or unless they are aged between 16 to 18 and moving within the European Economic Area.

Chelsea can still buy players during the period of the ban, but cannot register them to play for the club.