What are employee rights before signing a Performance Improvement Plan?

I am a Manager at a US-based IT company in Bangalore. I was placed on a Performance Improvement Plan (PIP) immediately after raising concerns about process violations, including cross-team bypassing, work being assigned to my team without my involvement, and peer managers overriding my authority. I believe this action may be retaliatory. Key Facts: • My current manager has supervised me for less than two months. • In April, he verbally described me as a Key Performer and stated that I was not a candidate for a PIP. • Concerns I raised during one-on-one meetings were later cited as performance issues. • The PIP was issued yesterday without any prior written warnings or documented performance concerns. • The PIP contains a termination clause that becomes effective upon signing. • The Vice President declined to meet with me, and HR appears to be supporting management's position. • I have not signed the PIP. I require urgent legal advice on whether this situation could amount to retaliation under Indian law, what my rights are before signing the PIP, whether I may take medical leave while on a PIP, and how I should respond to protect my legal interests.