Liverpool's former managing director Christian Purslow claims the Reds risk losing boss Jurgen Klopp to another top club unless they begin to match the German's ambitions.
In particular Purslow is concerned that Liverpool keep offloading their best players and do not bring in high-quality replacements.
"They [United] are shopping at Harrods - I do not know why he is making excuses by the way - Liverpool need to start shopping at Harrods rather than just selling the good ones," said Purslow, who was MD at Anfield between 2009 and 2010.
"And I really believe Jurgen Klopp is absolutely A-list, he is the next manager for one of those bigger clubs if Liverpool do not fulfil his ambitions."
"It is not a Big Six - it is a three and a three. It feels to me like City, United and Chelsea are breaking away from Liverpool, Arsenal and Tottenham for pure economic reasons," Purslow told The Debate.
"United are what Jose was on about, you are talking Paul Pogba, the most desired footballer on the planet went there last summer.
"The most productive centre-forward in the Premier League, Romelu Lukaku, went there last summer. Henrikh Mkhitaryan, probably the most admired creative midfield player in Germany, went there."