By Osasu Obayiuwana BBC Sport

Samuel Eto'o models the kit designed for Cameroon

Fifa has asked Cameroon's football Federation (Fecafoot) to explain the reasons for using banned kit during their African Cup of Nations quarter-final tie against Nigeria.

In a letter sent to Fecafoot on 13 February, they have asked for "further explanations" behind their inability to comply with an order, made in a letter dated 30 January.

The 30 January letter gave the former African champions special dispensation to use their kit, which combined a shirt and short into a single piece of apparel, for the group stage only.

Cameroon must respond by Wednesday Fifa spokesman Nicolas Maingot

This dispensation was given despite the statement of Fifa president Sepp Blatter that the kit, designed by sportswear manufacturer Puma, was illegal.

"This kit violates the rules of the game, which says each player must wear a shirt, short and socks," Blatter told BBC Sport in an exclusive interview on 22 January in Tunis.

Fifa spokesman Nicolas Maingot said Fecafoot have until 18 February to explain why they were unable to comply with their order.

"The Cameroon federation must respond to our enquiry by midnight (2300 GMT) on Wednesday at the very latest.

"This matter will be subsequently discussed by Fifa's disciplinary committee at a date which is yet to be decided," Maingot said.