I recommend the related answer by Joseph C Lee at https://www.researchgate.net/post/Unethical_act_of_Reviewer , and you may also look into two other related discussions that I indicated there.
1. I do the requested changes (I include the requested citations)
2. Than in the cover letter of the corrected manuscript, I indicate it to the editor(s) and ask his advice to decide to keep these citations, or neglect this point of the reviewer.
3. Option: I contact the reviewer, and discuss it with her/him and if these citations are important for her/his carrier or in worst case, important to keep his/her job, than I let this citations included. (only to help the reviewer who worked on my MS for free).
PS. if you work in very special themes, topics, not easy to find reviewer. Generally, I am grateful for teh reviewers who offer her/his time and energy tomake my MS better, it is always important!
Attila Haris is more generous and diplomatic than me!
I think this behaviour is very terrible and makes me quite sad because I have never done something like that as a reviewer. They make the rest of us reviewers sound bad!
As I indicated previously, I would follow these two steps:
STEP 1
Contact the editor or editorial manager to show their reviewer is unethical
STEP 2
Withdraw your paper from that journal and submit it elsewhere - unless you really want to get published in THAT journal
I would be most pleased to hear about your decisions and outcomes. I totally support authors that have to deal with bad reviewers.