Mancini eager to hit January sales to keep title race lead

City manager feels pressure of not previously winning the League will hit players

Roberto Mancini, the Manchester City manager, has expressed concern at the spending limitations being placed on him this month and declared that his club need to buy again now if they are to drive home their ascendancy over Manchester United.

As City prepare for an FA Cup third-round tie with United on Sunday which could do irrevocable damage to opponents already stung by October's 6-1 Premier League defeat, Mancini said he had been told he could not buy this winter. Behind the scenes, the manager is understood to have virtually resigned himself to Uefa's new Financial Fair Play (FFP) regime ruining any hopes of adding immediately to his squad.

But with City possibly reduced to one fit striker and only two holding midfielders for Sunday's tie, the manager insisted that his club would be under far greater pressure than United in the next four months and must spend to win the title. "Yeah, yeah. This is the problem," Mancini said when asked if he had been told he could not buy. "But if we don't have the players, it's tough for us. We are not United. The difference is this. United and Chelsea have won trophies for many years. So they are quiet. They understand that they can play without pressure. For us it's different. This could be the first championship for many years and we need to do everything we can to win it."

At the halfway point of the season, Mancini is acutely conscious of the relative calm with which the prospect of another title would be perceived at United, compared with the pressure which will build at City – after 44 years without a championship triumph. "United have won 19 championships," he said yesterday.

City's recent £195m losses leave them with a huge financial deficit to close to meet the FFP target of a maximum £45m aggregate losses over a three-year monitoring period, which started this season. Mancini still insisted City "could take in one player" and any aspiration to pay the high wages of Roma's Daniele de Rossi now appears to depend on whether Carlos Tevez can be shipped off. Milan are the Argentine's preferred location, with Internazionale also waiting in the wings. City's Abu Dhabi owners consider it a point of principle that Tevez should not be allowed to secure himself a cut-price move, having removed himself from Manchester, though a sale price of £20m – rather than £30m – may be in Mancini's interests, if he wants to buy.

"I think it's better that we sell first. Maybe then we can take in other players," he said. De Rossi has offered an intriguing hint of genuine interest in the Premier League by admitting, in a conversation at his own daughter's school, that he is undergoing English lessons.

Mario Balotelli is unlikely to shake off an ankle injury in time for Sunday, a knee problem to Edin Dzeko is causing concern and Samir Nasri is struggling with illness. But the biggest blow of all came yesterday lunchtime when the Ivory Coast coach, François Zahoui, a contact of Mancini's, rejected City's requests to play Yaya and Kolo Touré in the Cup tie, ahead of their departure for the African Cup of Nations. Zahoui insists the two must report for a meeting in Paris tomorrow before flying with the rest of the squad to Abu Dhabi for a two-day training camp.

"The national team in Ivory Coast is led by people who are well-educated and I was surprised that people in England think that we don't know the Fifa rules about dates," said Zahoui. "Here, when we call up the players, they are obliged to turn up at the date indicated by Fifa. So when we call them up we know that the clubs need to let them go."

With Owen Hargreaves' fitness levels an enigma – "I hope he can be ready to play one game but it depends on him. He is not Yaya at this moment," Mancini said – and Gareth Barry suspended, Mancini may have only James Milner and Nigel de Jong as conventional holding midfielders for the United game and yesterday also raised the possibility of the world's richest club not being able to fill their bench.

"If we have strikers injured then we need to buy another," Mancini added. "At the moment I have one striker because Dzeko has a problem in his knee. I have one striker and two midfielders. This month we are losing two players. If we lose another then we will need more players."

Mancini said he could not recall three successive defeats – the prospect facing Sir Alex Ferguson if his side lose on Sunday. "I don't remember when I lost three matches in a row," he said. "After two defeats, maybe another one would be a problem but they are very strong."

City limits: Mancini's absentees

Mario Balotelli (ankle injury)

Missed last two matches and is again likely to miss out on Sunday.

Edin Dzeko (knee injury)

Injured knee against Liverpool.

Owen Hargreaves (fitness)

Played three times since joining.

Samir Nasri (illness)

Severe doubt for visit of United.

Gareth Barry (suspension)

Banned after red card v Liverpool.

Kolo & Yaya Touré (African Cup)

Join Ivory Coast squad tomorrow ahead of African Cup of Nations.