Chelsea s French midfielder N Golo Kante runs with the ball during the English Premier League football match between Chelsea and Tottenham Hotspur at Stamford Bridge in London on August 14, 2022. (Photo by Glyn KIRK / AFP)
Kante, 32, has a history of injuries and missed six months of Chelsea's Premier League season with a hamstring problem.
The Al-Ittihad source said Kante had signed a binding agreement but the club were examining the results of medical tests before agreeing a final deal.
On Tuesday, the Jeddah-based club officially unveiled 35-year-old French Ballon d'Or-winner Karim Benzema as the biggest signing in their history.
"Kante signed a binding agreement, not a final contract," the source said.
"We still review the medical checkup result. He has a long injury history and we want to be careful before signing a huge contract."
Benzema's signing came after Portuguese superstar Cristiano Ronaldo joined Saudi Arabia's Al-Nassr in January in a deal said to be worth more than 400 million euros ($431 million).
Benzema and Kante are on a list of around 10 targets who have been contacted by Saudi officials, a source close to the negotiations told AFP last week.
Argentina's Lionel Messi announced on Wednesday he had turned down a blockbuster deal in Saudi Arabia in favour of joining MLS side Inter Miami.
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