LONDON (Reuters) - Former Manchester United boss Alex Ferguson has paid tribute to outgoing Arsenal manager Arsene Wenger, describing the long-serving Frenchman as "one of the greatest Premier League managers".

Wenger announced on Friday that he would leave Arsenal at the end of the season, bringing an end to his near 22-year reign at the north London club.

Tributes to Wenger poured in from all quarters, but Ferguson's words are particularly poignant given the longstanding rivalry between the two men who often clashed before the Scot retired in 2013.

"I am really happy for Arsene Wenger. I have great respect for him and for the job he has done at Arsenal," Ferguson said in a statement on United's website.

"It is great testament to his talent, professionalism and determination that he has been able to dedicate 22 years of his life to a job that he loves.

"In an era where football managers sometimes only last one or two seasons, it shows what an achievement it is to serve that length of time at a club the size of Arsenal.

"He is, without doubt, one of the greatest Premier League managers and I am proud to have been a rival, a colleague and a friend to such a great man."

The 68-year-old Wenger won three Premier League titles and seven FA Cups, including domestic doubles in 1998 and 2002, but bows out with Arsenal in sixth place in the Premier League ahead of Sunday's match against West Ham United.

Wenger's team face Spain's Atletico Madrid in the first leg of their Europa League semi-final next week.

(Reporting by Simon Jennings in Bengaluru, editing by Ed Osmond)