Pepe Reina has criticised Liverpool's handling of his Anfield exit and claimed he "deserved better" after the club agreed a loan deal with Napoli without his knowledge.

Liverpool's first choice goalkeeper since 2005 has joined the Italian club on a season-long loan after a proposed move to Barcelona collapsed earlier in the summer and the manager, Brendan Rodgers, made his new £9m signing Simon Mignolet his No1. In an open letter to supporters on his website, Reina accepts Liverpool's right to decide his future but expresses disappointment at being informed of the move to Naples only after the two clubs had arranged the deal.

Rodgers has said he took the pre-emptive step of signing Mignolet having been informed by Reina's representatives to expect an offer from Barcelona. That did not materialise after Victor Valdés opted to stay with the Spanish champions for another season and Reina, while confirming his interest in Barcelona, insists he told Rodgers he wanted to sign a new contract at Liverpool in the absence of a return to Spain.

"If I have one regret, it is the way that I am leaving," Reina wrote. "It is only natural that I would be disappointed that the Liverpool management agreed to loan me to Napoli without telling me first. I thought that I deserved better than that even though I understand that difficult decisions have to be taken in football.

"A lot has been made about me informing the club that if an offer came in from Barcelona that I would have liked them to consider it. But I had also spoken to the club about the possibility of extending my contract if the offer was not made. I told the manager that I wanted to play for Liverpool and that Barcelona would only become an option for me if the opportunity arrived, like the rumours said it would, as it would be a chance for me to go back home. When it didn't come I was happy to fight for my place, so I was surprised that Liverpool decided it was in the club's interests to send me to Napoli instead.."

Reina's Liverpool future was in doubt last season owing not only to Barcelona's interest but his £110,000-a-week salary and a drop in his previously commanding form. Despite the regret at the manner of his Anfield departure, the Spain international admits a reunion with the former Liverpool manager Rafael Benítez in Italy is a major attraction.

He added: "None of this will change my feelings for the club or the people in any way and now I have to look forward to a new challenge with Rafa Benítez, who I consider to be the best manager I have worked with, and I am fortunate to be going from one great club to another. Napoli remind me in many ways of the Liverpool I found in 2005, in all the affection they have shown me on my arrival, in having an ambitious project, even in coinciding and working with Benítez again."

Liverpool have declined to comment on Reina's letter, in which he says he hopes to say goodbye "properly" in the near future and does not rule out the prospect of playing for the club again. "Although it was not my decision to leave I will accept it just like I have always accepted any decision that Liverpool have taken for me," he states. "They signed me, picked me, gave me some of the best experiences of my life and looked after me. If they feel that the best thing for me and for them is for me to go on loan to Napoli for a season then so be it. Napoli is a new challenge for me and I know that the fans are just as passionate about their team as the Liverpool fans, so I am really looking forward to playing for them this season and I will give my all."

Reina writes at length of his deep affection for Liverpool and his admiration for the Hillsborough campaigns. "I may not have won as many trophies and medals as I would have liked since joining in 2005 but the experiences I have been a part of are as important as any silverware," he states. "I now understand how supporters can lift a team and inspire them to do special things. I appreciate that there is something unique about Anfield and the atmosphere it creates. I believe that anything is possible no matter what the situation is because at Liverpool there is no such thing as a lost cause. And I have been humbled by the fight for justice for the 96 which showed me that the Liverpool people will always fight for what they believe in."