The 29-year-old, who scored 15 goals in 44 games for the Blues last season, will have all his wages covered by Inter, while Simone Inzaghi's side will pay Chelsea a loan fee of £6.9m plus £3.5m in bonuses if they win the Scudetto.
Lukaku, who says he was in contact with Inzaghi throughout last season, says it feels like "coming home" after re-joining the club.
"I didn't even leave my home when I went to England, which shows how happy I am to be back here," he added. "Now I just want to see the guys on the pitch."
The Belgium international's delight at leaving Chelsea after a mediocre campaign in the Premier League has brought plenty of comments from fans on social media.
Kinsella claims the pair were watching a game involving Spurs when Tuchel made a "daddy" comment about former Inter Milan manager Antonio Conte. It didn't go down well.
"To see him talk so highly of Inter [during the Sky Italia interview] was an insult to Chelsea fans. It broke the relationship with them," he said.
"And there was another incident behind the scenes that wasn't televised or anything like that.
"Someone told me that Lukaku and Tuchel were watching a Tottenham game and Tuchel said, 'There's your daddy', about Antonio Conte. It was just a joke, but apparently, it didn't go down very well with Lukaku."
You can see the full clip of Kinsella speaking about the incident below.
:rotating_light: ATTENZIONE :rotating_light:- The Italian Football Podcast (@ItaFootPod) June 29, 2022
:speaking_head: #LukakuIsBack @Inter_en w. @NizaarKinsella
- #LukakuDay breakdown of move :moneybag:
- Why it went wrong at #ChelseaFC
- #Tuchel joke to #Lukaku "#AntonioConte your daddy" :flushed:
- How good will #LaDyLuk be at #Inter w #Dybala & #Lautaro be :fire:
Much more pic.twitter.com/BDuzpWeV0v
Italian outlet Gazetta dello Sport claim he became emotional when his lawyer Sebastien Ledure broke the news about his move after talks had stalled when Inter president Steven Zhang attempted to restructure the financial package.
The striker has agreed to a 30 per cent pay cut in order to secure a move back to the San Siro.
Featured Image Credit: Alamy
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