File Photo: Morocco midfielder Azzedine Ounahi. AFP
The fee for Ounahi, who starred as his country reached last year's World Cup semi-finals, was not made public but media reports claim Marseille will pay 10 million euros ($10.9 million) for the 22-year-old.
"Marseille announce an agreement in principle with @AngersSCO for the transfer of @AzzedineOunahi," the Ligue 1 club said on Twitter.
He is set to become Marseille's second signing of the January transfer window after Ukraine international Ruslan Malinovskyi.
Ounahi featured in all of Morocco's games as they made a surprise run to the last four of the World Cup, becoming the first African and Arab team to reach the semi-finals.
Following his performances in Qatar he was linked with a move to Sevilla, Napoli and Leicester.
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