URS and change control

Hi dear experts,

It would be appreciated to assist me for the case below:

Part of a qualified machine need to be change as its weight should be made lower than it’s current state by changing mechanical design but the function will not be changed.

Should a requirement as’ the part should have a lower weight up to 2kg’ be added to the URS doc?
should the part be weighted in IQ test to ensure it has been designed as stated in the URS?
Since a new part is designed then its function should be checked during OQ test. Right?
should RTM be updated because a new requirement is added to the URS?

Regards,

Your reply will be highly appreciated