Attorneys for Kaci Hickox, 33, said they had not yet been served with a court order to enforce the 21-day quarantine - matching the virus's maximum incubation period - but remained prepared to fight such an order if necessary.
LePage's office said negotiations with Hickox, who worked with Doctors Without Borders in Sierra Leone, "have failed despite repeated efforts by state officials" and that he would "exercise the full extent of his authority allowable by law."
The quarantine showdown between Hickox and Maine has become the focal point of a struggle between several U.S. states opting for stringent measures to guard against Ebola and a federal government wary of discouraging potential medical volunteers.