City - fourth in the table heading into Monday's trip to Crystal Palace - appear destined to relinquish their Premier League crown as Chelsea top the standings by nine points ahead of Pellegrini's men with eight matches remaining.
Pellegrini faces an uncertain future with City set for a trophy-less season after bowing out of the UEFA Champions League last month.
But the Chilean boss provided an insight into how City will approach the transfer window at the end of the 2014-15 campaign.
"It is the way of thinking that big teams need to sign a big player. It is very difficult to do it every year, but every two years you must do it," said Pellegrini, whose side can reclaim second spot with victory at Selhurst Park.
"I'm not just talking about Manchester City. You see Real Madrid, Manchester United, Chelsea, Barcelona and Bayern Munich – all the big clubs – they all do it. It is important to have big names.
"I don't want to talk about plans for next season because we have to finish this season. It is very important the way we finish this season before we analyse all the players. So it is not the right moment to talk about it."
