United are on the verge of completing a transfer for the 23-year-old that could cost them in excess of £100m.
"If you are making money and have to pay big money for the best players, why not do it?" Robson told BBC Radio 5 live's Sportsweek programme.
Manager Jose Mourinho wants the deal to be completed before 14 August.
No deal has been announced for Pogba, who has been on holiday in the United States since losing the Euro 2016 final with France against Portugal last month.
Juventus coach Massimiliano Allegri has said he expects the midfielder to be at training on Monday, although reports in Italy say Pogba has flown to the UK for a medical.
Manchester United have not responded to these reports.
Pogba played at United for three years before rejecting a new contract and joining Juventus for a £1.5m compensation fee in 2012.
He won the Serie A title in four successive seasons in Italy and has established himself as one of the most highly rated players in the world.
"Sir Alex Ferguson allowed me to watch training as Pogba joined the first team squad [as a teenager]," said Robson.
"I was very impressed with him. He was a good build, with a good temperament.
"He is the type of player we need.
"He is similar to Yaya Toure in the sense he is very good going forward and can score spectacular goals.
"I am not sure he is a great defender but he does an adequate job."
Subscribe to the BBC Sport newsletter to get our pick of news, features and video sent to your inbox.

El Hadary, who has just turned 44, came off the bench in Tuesday's 0-0 draw with Mali when El Shenawy hurt himself.
In doing so he beat the age record of 39-year-old compatriot Hossam Hassan.
BBC Sport has learned El Shenawy is out of the finals with a hamstring tear and Ekramy is being treated for a hamstring strain, leaving Egypt with no back-up.
Ekramy suffered his injury during training on 14 January and is undergoing intensive treatment in the hope he can recover to play if required.
Despite the critical situation, BBC Sport has been told the Egyptian Football Association will not seek to call up another goalkeeper to the squad because it believes it is not permitted under the Confederation of African Football's tournament regulations.
Caf's rules state that a replacement player cannot be called up later than 24 hours before a team's opening game of the tournament.

Jodie Wilkinson, 27, was attacked by a group of up to 11 men in Stanhope Street, Newcastle, on 11 October.
Sharif Kalimba, 19, of no fixed address, has been charged with violent disorder and remanded in custody.
Four men from Newcastle, aged 25, 25, 22 and 20, have been charged with violent disorder. David Waterston, 43, from the city, was charged with murder.
Mr Kalimba is due to appear at South East Northumberland Magistrates' Court on Monday.

Media playback is not supported on this device
Haskins was awarded the belt after Randy Caballero was stripped of his title after weighing in five and a half pounds over the limit for last Saturday's fight, which had been due to take place at the Mandalay Bay Hotel.
Bristol-based manager, Chris Sanigar, told BBC Points West about his future hopes for 32-year-old Haskins.

Joedyn Luben, 32, had £77,000 in a safe at his home in Penlan, Swansea, he told Cardiff Crown Court.
He claims officers from South Wales Police stole £30,000 of this during the raid in April 2011.
Det Sgt Stephen Phillips, 47, of Swansea, Det Cons Christopher Evans, 38, of Llangennech, and Michael Stokes, 35, from Glynneath, deny theft.
Mr Luben told the court on Tuesday he gave the code to the safe to Det Con Stokes when asked by the officers.
He said he had been saving the money since he was 16 and last used the safe the night before the raid, when he deposited £12,000 following the sale of a car.
No action was taken against Mr Luben so a cheque was written for him to return his money.
However, he said this was £30,000 short of what was seized.
The case continues.
Former Manchester United captain Bryan Robson says he has no problem with the club breaking the transfer world record to re-sign Paul Pogba from Juventus.
[NEXT_CONCEPT]
The oldest Africa Cup of Nations player Essam El Hadary is Egypt's only fit goalkeeper in Gabon after injuries to Ahmed El Shenawy and Sherif Ekramy.
[NEXT_CONCEPT]
A further man has been charged in connection with the fatal stabbing of a woman, bringing the total to six.
[NEXT_CONCEPT]
Britain's Lee Haskins could return to Las Vegas for a big pay day after winning the IBF world bantamweight title without throwing a punch.
[NEXT_CONCEPT]
Three detectives stole a man's life savings in a raid on his home, a court has heard.