United had agreed a £25.5million fee for the 25-year-old and had made the former West Ham star a five-year contract offer.
Manchester City and Chelsea are now the two clubs int he race to sign the striker.
“When Man United made their offer about ten days ago, for the first time in two years, we never went back to them to ask about money,” Joorabchian told Sky Sports News.
“We just asked for some time to think about it. Obviously they have had two years to think about it and Carlos had to make a decision based on his family.
“Just to make it clear, this has been Carlos’ decision. Nobody else would make this decision for him.”
Joorabchian added: “We didn’t actually reject the offer. Manchester United have ruled themselves out of the running.
“We actually asked for more time and if they could not give that we would have to walk away.
“He wants time to digest it and to know which club would suit him because now he is committing the next five years of his future.”