Barcelona are set to splash the cash when the transfer window reopens at the end of the season.
The Catalan giants are in sore need of reinforcements after their 3-0 Champions League defeat to Juventus on Sunday.
Fierce rivals Real Madrid are also set to invest heavily in new signings, with Antoine Griezmann and Chelsea star Eden Hazard heavily linked.
Lionel Messi wants Barcelona to sign four players this summer Barcelona wages revealed: Which stars earn most? Fri, March 24, 2017
Click to reveal every Barcelona player's weekly wages, according to Totalsportek.com
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Click to reveal every Barcelona player's weekly wages
And Spanish outlet Diario Gol claims Messi wants four signings in order to ensure they keep up with Zinedine Zidane's side.
The Argentina international wants the Catalan giants to sign a right-back – believing they have not sufficiently replaced Dani Alves since his exit last summer.
He also wants a midfielder to relieve some of the pressure on Andres Iniesta.
Lionel Messi thinks Barcelona have failed to replace Dani Alves
Iniesta turns 33 next month and PSG's Marco Verratti and Liverpool's Philippe Coutinho have both been backed to replace him.
Messi wants a new centre-forward with Paco Alcacer struggling since arriving from Valencia last summer.
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And he also wants Barcelona to sign a centre-back amid Jeremy Mathieu and Javier Mascherano's inconsistent form.