Home Minister Muhyiddin Yassin will resume office next week following as his condition has greatly improved, his press secretary has said.

In a statement uploaded to the minister's Facebook page today, his press secretary Hafiz Abdul Halim stated that the former will be sworn as the Pagoh Member of Parliament on Aug 14.

Muhyiddin had been on a lengthy medical leave since mid-July after successfully undergoing an operation to remove a growth in his pancreas, which Hafiz had previously stated had been detected at an early stage.

In his absence, his ministerial duties had been assumed by Prime Minister Dr Mahathir Mohamad.

"Upon the doctor's advice, he (Muhyiddin) will undergo follow-up treatment, including chemotherapy, for up to six months as a precaution to ensure the growth does not recur.

"The Home Ministry's office wishes to inform that Muhyiddin's official duties would be limited throughout his treatment. This is to ensure he undergoes the treatment properly and fully recovers," the statement read.

This comes after Mahathir had revealed last night that Muhyiddin, who is also Bersatu president, could be undergoing chemotherapy.

"I visited him... he is well. This kind of disease... the treatment period is very long... he will have to do some follow-up and maybe (he will undergo) chemotherapy," Mahathir had said.