Manchester United boss Jose Mourinho has insisted that Jurgen Klopp is right to be questioned about the fee Liverpool paid to sign Virgil van Dijk from Southampton.

The Reds have splashed out a record amount of money for a defender after agreeing to pay £75m when the transfer window officially opens for business on January 1.

Two days on from the transfer announcement, Mourinho has accused opposite number Klopp of hypocrisy as the German has previously criticised United for spending big to sign Paul Pogba.

"I think the ones that speak about it in a specific way has to be Jurgen. And if I was one of you I would ask him about his comments about one year ago," he told reporters. "But not speaking specifically about that case, because in Liverpool they do what they want to do, and I am nobody to comment on what they do.

"The reality is that if they think that the player is the right player for them and they really want the player they pay his amount or they don't have the player because that is the way the market is at that time. So when we compare now the amount of money certain managers and clubs spend, to try to compare that, I am not saying even 10 years ago, but even three years ago, is to compare the impossible.

"You cannot compare the realities. Van Dijk is the most expensive defender in history of football. Was he better than Paolo Maldini, Giuseppe Bergomi or Rio Ferdinand? You cannot say that, it's just the way the market is, and you pay or you don't pay.

"If you pay, obviously you pay a crazy amount of money, but if you don't, you don't have the player. It's as simple as that, so no critics at all about what Liverpool did, it's just the way it is."

Klopp has defended the amount of money paid to sign Van Dijk, who initially came close to making the switch between clubs in the summer window.