The Bolton brawler erupted after reacting to comments made by the 28-3 Canadian about well-documented troubles in his personal life in recent years.
“The defeat by Canelo started a losing streak,” Lo Greco said.
“Then he lost his family, his wife and then he posted on Twitter telling the world heavyweight champion he could have his leftovers.”
Former light-welterweight champion Khan bolted to his feet before launching a glass of water at Lo Greco, sparking a vicious confrontation on-stage.
Promoter Eddie Hearn was almost bowled over by security staff as the two men had to be restrained from coming to blows at the event in Liverpool this lunchtime.
Security staff managed to bring the two men back under control and they returned to their seats shortly after.
Lo Greco apologised to the crowd inside the Liverpool hotel – but they were unforgiving in shouting him down before Khan too apologised for losing his cool.
The April 21 showdown will be only the second fight in almost three years for 31-year-old Khan, having been emphatically beaten by Canelo Alvarez in May 2016.
“I can’t wait to get back into the ring on April 21 at the Echo Arena in Liverpool,” the 31-4 fighter said.
“Phil Lo Greco will be coming with everything to win this fight and I’m not going to give him an inch. He’s an aggressive fighter who is always looking to press the fight and come forward.
“That makes for a very exciting and action-packed fight for the fans.
“I respect him as a fighter and know he will be coming with big ambitions, but I’m going to put on a great performance and prove to the boxing world that the ‘King’ is well and truly back.”
