Six Arab football federations backed Gianni Infantino on Thursday, giving the FIFA president a show of support as opposition to his leadership grows following the collapse of a controversial private investment plan involving the World Cup.

The federations of Morocco, Qatar, Egypt, Mauritania, Lebanon and Sudan said they had "full support" and "confidence" in Infantino and praised his efforts to expand the global reach of the sport.

"We, the undersigned leaders of our respective football associations, express our full support for Mr. Gianni Infantino, President of FIFA, and reaffirm our confidence in his leadership and continued commitment to the development of football worldwide," the federations said in a joint statement.

The statement also praised Infantino for advancing football in different regions and strengthening its role in bringing communities together.

The endorsement came as Infantino faces his most serious challenge to his leadership since becoming FIFA president in 2016. He is seeking a fourth term at next year's FIFA Congress in Morocco and had appeared certain to win re-election unopposed before the dispute over the investment proposal triggered a backlash across several confederations.