Gareth Barry, who made a record 653 appearances in the Premier League, called curtains on a 23-year-long career.
The Qataris say they are ready to host the tournament in summer or winter and will work to secure the "agreement of the international football community".
Qatar won the hosting rights three years ago despite the bid being declared "high risk" by FIFA's own inspection team, which highlighted the searing summer heat in the Persian Gulf where temperatures can hit 50 degree Celsius (120 F).
Although Mancini is keen to start his transfer business quickly, he insists now is not the time to discuss whether Carlos Tevez or Gareth Barry, who each have a year left on their contracts, will be getting new deals.
The Italian, who won the FA Cup in 2011 before winning the Premier League title last season, has previously boasted about his record of having won silverware in each of his full seasons as a manager.
Roberto Mancini's team have responded to their 3-2 defeat in the Manchester derby earlier this month with consecutive victories.
Barry is believed to have been angry that referee Martin Atkinson gave United a free-kick for Carlos Tevez's challenge on Rafael da Silva, an incident which allowed Robin van Persie to fire in the stoppage-time winner from the set-piece.
Manchester City midfielder Gareth Barry has been charged over his behaviour during his side's 3-2 loss to Manchester United, the Football Association announced on Tuesday.
Mikel had admitted using threatening and/or abusive and/or insulting words and/or behaviour in the official's changing room at the end of the game at Stamford Bridge on October 28, said the Football Association.
England midfielder Joe Cole said Monday he would love to finally prove himself at Liverpool after a successful loan season at French club Lille.