Obtained by Kotaku, the message was sent to all Ubisoft employees at its offices around the world.
Throughout the letter, Guillomont shows his gratitude to Ubisoft's staff both locally and globally, and praises how everyone has adapted to remote working in such a short space of time. He also states that the firm has "sufficient cash reserves" to weather the storm.
"We are now in a pandemic, with far-reaching effects on our daily lives," reads the letter.
"At this exceptional juncture, it is essential that we take special care of ourselves and our loved ones. The health and well-being of Ubisoft team members is our primary concern, and we have taken the necessary steps to ensure that all of you are safe and get the right support through these demanding changes. In particular, we have been encouraging all of our collaborators to work from the safety of their homes since the end of last week.
"Across Ubisoft, people are going above and beyond to adapt to this unprecedented event. My warm thanks go to both your local and global management teams, who have done such remarkable work in implementing the required preventative measures, in line with recommendations from national authorities and the World Health Organization.
"I also want to commend the proactivity of our teams who have gone to great lengths to provide us with solutions to work from home under the best possible conditions, thus ensuring the continuity of our operations."
"Everyone has a role to play, and this includes taking the necessary precautions to protect ourselves and people around us," continues Guillemot.
"I believe we can learn a great deal from our teams in China, who have faced the same trials a few weeks before us: the experience of our Chinese friends give us hope in showing that responsible behaviour and pro-active public health measures can lead us out of the crisis.
"We will continue to provide you with regular updates as we move forward. Your local managers and I are also available should you have questions or concerns. In the meantime, please take care of yourself."
After the cancellation of E3 2020 due to the coronavirus, Ubisoft revealed it wIll look at digital events to replace the event.
Prior to this, Ubisoft took another step into the world of mobile games with the acquisition of mobile developer Kolibri Games.