The 30-year-old returned to the Blues in a £97.5m deal from Inter Milan in the summer of 2021, but he found it difficult to make his mark during the 2021-22 campaign, only managing 15 goals in 44 appearances.
Lukaku returned to Inter on loan last summer, and he represented the club on 37 occasions, scoring 14 goals and registering seven assists in the process.
The Belgium international had been in discussions over a return to Inter, but it is understood that the Italian side have now dropped their interest, having learned that the striker was also speaking to Juventus.
There is also thought to be a host of Saudi Arabian interest in Lukaku, and it has now been confirmed that he will be leaving Chelsea this summer.
"It is the club and of course it is an interesting situation," Pochettino told reporters. "When this type of decision is [made, it is] because they all agree. The player and club are working hard to try and find best solution.
"It is obvious the decision had been made on the side of the player also. We act in consequence of the decision. The club and player are in the position they wanted."
Lukaku has not travelled with the Chelsea squad on their pre-season tour of the United States, with the forward attempting to engineer an exit in the coming weeks.
The forward initially made the move to the Blues from Anderlecht in 2011, but a disappointing first spell at Stamford Bridge saw him fail to score in 15 appearances.
Pierre-Emerick Aubameyang is also believed to be on the verge of leaving Chelsea, with Marseille said to be in talks with the experienced forward over a move.
There have been four attacking additions at Stamford Bridge this summer, with Christopher Nkunku, Nicolas Jackson, Diego Moreira and Angelo Gabriel moving to the club.
There have been a number of departures, meanwhile, with Kai Havertz, Mason Mount, Mateo Kovacic, Kalidou Koulibaly, Christian Pulisic, Edouard Mendy, Ruben Loftus-Cheek, Ethan Ampadu, N'Golo Kante, Cesar Azpilicueta and Baba Rahman all moving on.
Chelsea will begin their preparations for the new campaign with a friendly against Wrexham on Wednesday night before also taking on Brighton & Hove Albion, Newcastle United, Fulham and Borussia Dortmund.
Pochettino's side are building towards their Premier League opener against Liverpool on August 13.