Boris Johnson is likely to undergo several crucial tests, including checking oxygen levels and organ function before he is released from hospital, according to doctors.
His white blood cell count and liver and kidney function will be analysed and the PM is likely to undergo an electrocardiogram to check his heart.
Johnson was taken to hospital on Sunday night as a precaution with him still displaying symptoms of coronavirus 10 days after being diagnosed.
GP Dr Sarah Jarvis told the BBC the Prime Minister would also have his chest X-rayed and lungs scanned, particularly if he was found to be struggling for breath.