The Ivory Coast expect Manchester City pair Yaya and Kolo Toure to report for international duty on Saturday, which will mean the brothers will not be available for Sunday's FA Cup derby with Manchester United.
Blues boss Roberto Mancini earlier on Thursday hoped the pair would be allowed to join the Ivory Coast squad for January's African Cup of Nations slightly later than planned, which would allow them to feature in the third round tie at the Etihad Stadium.
Mancini expected to learn within 24 hours whether the Toures would be excused a planned squad gathering in Paris on Saturday before they fly to Abu Dhabi for a two-week training camp.
City were unaware of any official developments this lunchtime, however, Ivory Coast coach Francois Zahoui has apparently declined Mancini's hopes.
"Clubs know the rules," said Zahoui. "I'm expecting them [the Toures] for the FIFA deadline."
If confirmed, the news will be a major blow for City, whose manager has revealed he may struggle to fill his bench on Sunday.
Gareth Barry is suspended, Owen Hargreaves is not considered fit enough to be involved and Mario Balotelli is troubled by an ankle injury that prevented him playing against both Sunderland and Liverpool.
"We have 17 players," said Mancini. "I do not know how it is going to work.
"I always said we could have a problem in January. Yaya is an important player for us.
"Kolo is different. We have eight defenders and, if we are lucky, we don't have any injuries.
"In midfield we have a big problem. On Sunday, we only have James Milner and Nigel de Jong available."