Steven Nzonzi (L) most recently played on loan for Rennes before his move to Qatar (AFP)
Nzonzi, 32, who came on as a substitute in France's 2018 World Cup final win over Croatia, joins a long list of prominent internationals to move to the resource-rich Gulf emirate including Xavi and James Rodriguez.
Local media reported Nzonzi, who most recently played on loan for French top-flight side Rennes, had signed on for two years for an undisclosed amount.
He was due to be formally unveiled at an event at the club at 1300 GMT following a medical assessment.
Last week Colombian midfielder James Rodriguez, 30, left Everton to join Al-Rayyan for an undisclosed amount after falling out of favour at the Premier League club.
Nzonzi, capped 20 times by France, will be united with his countryman and Al-Rayyan coach Laurent Blanc who previously managed Paris Saint-Germain which is now under Qatari ownership.
Nzonzi has also played for English sides Blackburn Rovers and Stoke City as well as Sevilla and Roma.
Al-Rayyan, who have been Qatari champions eight times, are currently eighth in the league out of 12, with just three points from four matches.
The transfer window for Qatar's top flight remains open until September 30.
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