Jose Mourinho’s United bought Paul Pogba for a world record fee of £89million (€104.7m) and Pep Guardiola’s City made big outlays on players including £50m (€58.8m) defender John Stones. But both sides are battling for Champions League football next term.
Chelsea were third in Premier League spending last summer — their £123m (€144.7m) outlay was behind City’s £174m (€204.8m) and United’s £149m (€175.4m) — but sit four points clear of Tottenham with six Premier League games to go.
Conte, whose side play Southampton tonight, said: “This season it’s very important to understand that it’s not always about who spends more money who wins.
“This season isn’t the only season both Manchester clubs have spent a lot of money. Look at the past.
“It’s right for them to do this, to reinforce their teams, if they think this is the right way to win the title.
“(But) every single club decides their own strategy.”
Chelsea last summer signed N’Golo Kante for £32m (€37.6m) from Leicester, last season’s champions.
Kante has shown he is a crucial part of the Chelsea team and the midfielder was on Sunday named the Professional Footballers’ Association player of the year.
Conte has spoken repeatedly of Chelsea being in a transitional period with Branislav Ivanovic and John Obi Mikel having left and club captain John Terry leaving this summer.
Chelsea are seeking leaders and Kante is one, but not in the traditional sense.
“He’s a silent leader and a leader on the pitch by example,” Conte added.
“He’s not the type of player who likes to speak (out). He’s not John (Terry) in terms of his personality. He’s different.”
Conte urged his players to turn a good season into a great season by completing a Premier League title success ahead of the May 27 FA Cup final with Arsenal and a possible double.
The Italian added: “This season is very important because we are trying to build something important for the present, to put the foundations down and be strong, stronger for the future.
“And to build, also, slowly slowly to become a real power. A real power in the future.
“We must know that now it’s a good season. To become a great or fantastic season there is only one way: To try to win.”
Conte wants Eden Hazard to continue to put the team before himself.
The Belgium playmaker made a decisive impact as a substitute as Chelsea beat Tottenham 4-2 in Saturday’s FA Cup semi-final.
Afterwards Cesc Fabregas stated his belief that Hazard was second in ability only to Barcelona’s Lionel Messi and can improve if he is more “selfish” and shows a greater “killer instinct”.
But Conte reckons players can only be great by playing as part of a team.
“The first target for every great champion is to play for the team and to put your talent in the team,” Conte said.
“I don’t think that a player like Messi is a selfish player. The best players in the world don’t exist without the team.
“For me, it’s sad when I listen to this, that one player must be more selfish to reach the top level. This is not my idea of football. I never will understand this. Never.”