Mr Cook said that despite a smooth transition to remote working, it was not an adequate replacement for in-person collaboration.
"For all that we've been able to achieve while many of us have been separated, the truth is that there has been something essential missing from this past year: each other," he said in the document, seen by
The Verge.
"Video conference calling has narrowed the distance between us, to be sure, but there are things it simply cannot replicate."
He added: "I know I'm not alone in missing the hum of activity, the energy, creativity and collaboration of our in-person meetings and the sense of community we've all built."