Sullivan had voiced concerns at the apparent slow progress being made in buying City by Honk Kong businessman Yeung who paid £15 million for an initial 29.9% stake last month.
But his representative Sammy Yu is adamant that Yeung could be the owner of the Blues within two months - and bring to an end the 14-year reign of Sullivan and chairman David Gold.
Yu said: "I appreciate that Mr Sullivan wants to ensure the stability of the club as soon as possible. We have no bad feelings about what was said in the week.
"But sooner or later it will happen. At the moment we are making sure we satisfy the regulations that all listed companies in Hong Kong have to abide by.
"We are definitely coming to Birmingham though and, from Hong Kong, we are monitoring all that is going on at the club.
"It won't take long and Mr Yeung stands by what he said in Birmingham last week. He feels that he could take control in a month or two so by October he could be the owner.
"A lot of things we need to do with the stock exchange in Hong Kong have been done already.
"We understand the concerns of the club and the supporters but we do not see there being any problems.
"It's just that we are not based in the United Kingdom and there are many small details that need to be completed which just take time."