A TL of a different team from my company wants my help regarding some work where I need to invest my time for that work. I am more than happy to help but I am told that I should keep any info about this work secret from my TL which I am uncomfortable with. My TL is really supportive and stands up for me and I am sure if I told him about this extra work from a different team, he will be supportive of it but I am told not to discuss or mention anything about this work with him (his reason being office politics). I'm not sure what to do, on one hand I want to help this guy with this work but on other hand I don't want to keep things secret from my TL. Please suggest what should I do