The firm that controls the real estate of St. Elizabeth’s Medical Center in Brighton rejected Gov. Maura Healey’s offer of $4.5 million for the property and told the state that it will “vigorously challenge” the governor’s plan to take the Steward Health Care hospital’s land by eminent domain.

The governor announced Friday that the state plans to seize the land to facilitate a transfer of the hospital to Boston Medical Center. The state offered the companies that control the hospital’s real estate $4.5 million on Friday “to purchase the fee and any other necessary property interests in St. Elizabeth’s Medical Center” as the first step towards an eminent domain taking of the land.

The companies — led by ACREFI CS U, LLC and including Medical Properties Trust and Apollo Global Management — rejected that offer in a letter late Tuesday, saying the state’s proposal “significantly undervalues the real property underlying St. Elizabeth’s” and represents an amount less than the property’s annual tax bill.

“Accordingly, should the Commonwealth move forward with its proposed plan to exercise eminent domain and compensate ACREFI only $4.5 million for the property, ACREFI will have no choice but to exercise its constitutional and statutory rights and take any and all actions necessary to protect the interests of the investors to which it has fiduciary obligations,” the letter from the lender says. “ACREFI believes there are numerous procedural and constitutional issues raised by the Commonwealth’s proposed plan and conduct to date that it will vigorously challenge.”

Healey’s office said that it is completing the legal work necessary to move ahead with an official order of taking.

“Steward and Apollo need to stop playing games with people’s health care. We are moving forward with plans to take St. Elizabeth’s by eminent domain,” a Healey spokesperson said Wednesday afternoon.