This week, West Ham confirmed Paqueta has been given permission to fly to Brazil to complete a medical ahead of a proposed £36.5 million transfer to Flamengo.
The 28-year-old, who moved to West Ham from Lyon in 2022, had a contract with West Ham until the summer of 2027 and the side even had the option of extending his deal by another 12 months.
West Ham cannot replace Paqueta
However, he will depart before the transfer window slams shut over the next few days in what is a huge blow for the relegation candidates.
Speaking in his latest press conference ahead of the clash with Chelsea this weekend, Nuno was asked about Paqueta, who he says is irreplaceable.
"If it was in another moment of the season, if we were not in the situation that we are. Two years ago we knew what happened with Lucas so many things have happened to come to this end.
"It could be done two years ago and everything would be different, but it is what it is, and we move forward."
On how important it is that West Ham replace Paqueta: "You cannot replace Lucas because he is unique. He is a number 10 that has special qualities. You cannot find many players like Lucas in the transfer window, you cannot find them. We have to move forward with that we have."
The deal is not done yet
Speaking further on the 28-year-old, Nuno revealed that the deal is not yet done, but it's clear that he wants to leave and there is nothing he can do about it. Paqueta is set to make the switch with the Brazilian top-flight starting in March.
"It's not official yet so we as a club have allowed him to travel to do his medical, but I think we will find a solution that everybody was aware and came to a good conclusion.
"Lucas was clear he wanted to return home, and we expect the medical and things to come official. Let's wait and see.
"For me, Lucas is a special player and a special person. He is a number 10 I tell you many times. I think in terms of club, it was not the proper way.
"I think everything could be different, but the circumstances is what it is. He wanted to go to Brazil, he had an offer, we expect the medical and you keep moving knowing he is a special person and player. We wish him all the very best."