Footage had emerged on social media where the managers and members of his side were seen going through training sessions that breached government measures which were put in place to contain the spread of coronavirus.
The UK government has adviced everyone to stay at least two metres away from others in public, however, Spurs defenders Davinson Sanchez and Ryan Sessegnon were pictured running side-by-side on Tuesday.
"I accept that my actions were not in line with government protocol and we must only have contact with members of our own household," Goal.com quoted Mourinho as saying.
"It is vital we all play our part and follow government advice in order to support our heroes in the NHS and save lives," he added.
Earlier, Tottenham faced backlash for deciding to cut the wages of all non-playing staff by 20 per cent in response to the coronavirus crisis.
On Tuesday, the number of coronavirus hospital deaths in Britain rose to 6,159, a record increase of 786 in a day, the British Department of Health and Social Care said.
So far, 55,242 people have tested positive in the country, an increase of 3,634 over Monday.
( With inputs from ANI )