Inter to extend his contract? I don't think they would plan to do such thing at the moment. Because Lukaku's recent performance was quite inadequate first of all. He played a big role in Inter's losing the Champions League in 90 minutes as well by wasting important chances. He is just an inconsistent player these days. We don't have the old productive striker Lukaku here. Maybe he isn't the same in his national matches. Because he is scoring many goals there with Belgium recently.
But this isn't enough to convince Inter as long as he doesn't reflect this performance onto his matches at Inter. Chelsea also don't seem to have plans for him so I wonder how he will end up this summer.
Romelu Lukaku was a total flop this season, netting just 14 goals with 7 assists in 37 appearances for Inter, which is completely understandable given his long-term injury this season; however, he did not deserve accolades because he was unable to rebound back to his peak. Inter experienced a different version of Lukaku when he returned to Italy; he's not the Lukaku who plays for Chelsea anymore; he's changed a lot. That's the concept; Romelu Lukaku doesn't seem a consistent player; he might do great one season and then flop the next; that's how these players are.