NHS Borders cancelled routine operations due to "extreme pressures at its main hospital".
Ralph Roberts, chief executive, stated that the Borders General near Melrose was full and that its emergency department was "exceptionally busy".
A Covid outbreak has also been reported in Peebles' Hay Lodge Hospital.
Roberts stated that all efforts would be made to prevent the need for emergency surgery and cancer.
He said, "This is a very difficult situation and our employees are working around the clock to care for patients."
"Our surge capacity plans have been in place. We can assure you that our staff is doing all they can to make beds and continue planned operations as quickly as possible."
He asked for the public's help by calling NHS 24 prior to going to the emergency room.
He said that while you may have to wait for your call to be answered, or for a member to call back, this can be done from the comfort of your home.
"If you are in urgent need of treatment, you might be offered an appointment to reduce the amount of time you spend in the department.
"This reduces the pressure on our team."
He stressed however that anyone who believes their condition is life-threatening should dial 999 immediately.
Roberts asked for the public's help to ensure that family members can return home as soon as they are able, when they are able.
