United have dispatched a delegation that will touch down in Brazil on Tuesday to open talks with Moura’s father after it emerged he’d been in touch with Inter Milan.
The Red Devil’s were initially told 19-year-old would join Spanish champions Real Madrid only for manager Jose Mourinho to pursue a move for Luka Modric instead.
Sir Alex Ferguson is now ready to step up his efforts to bring the Brazilian international to Old Trafford and wants the deal tied up before he links up with the national team at the Olympics next month.
Moura, who was the subject of a failed £32 million bid from Chelsea earlier this year, has suggested that he could leave the Morumbi this summer.
Lucas said: “I cannot guarantee that I will stay until the end of my contract.
“Much has changed and the situation is not up to me any more.
“I know my father and my agent had a meeting (with Inter) but I don’t know what was said. Now I will go to the Olympics with my mind only on winning a gold medal.”
Inter technical director Marco Branca and sporting director Piero Ausilio are believed to have spoken with Lucas’ representatives and are set to make a £20m offer but United are reportedly willing to pay £30m.
And Moura insists he will consult his family before deciding whether to leave Sao Paulo with two of Europe’s elite clubs vying for his signature.
He told Estadao: “You never know what can happen. I don’t have a crazy desire to leave but, when the time comes, I will speak with my family and decide what is best for my future.
“When I go on the internet I see Inter, Real Madrid and I don’t know who else, wanting to come for me with a truck load of money.
“Of course I think about it, but I can’t let it go to my head. I’m very calm and down to earth about it. My job is to play football so that these clubs continue to be interested.”