Notice Period Mismatch

Hello There, I started my IT career in 2003 and currently holding nearly 15 years of IT experience. Recently I joined at one of the US based IT companies at Hyderabad. I got soft copy of offer letter on 16th Feb 201 which I have accepted. As part of my soft copy of offer letter, it is clearly mentioned that "First 3 months would be a Prohibitionary period" During this period, if employee submits resignation, Notice period would be 1 week. I have joined this company on May 18th and got a hard copy of offer letter on the day of joining. On the hard copy, my employer has removed the prohibition period concept and it is mentioned that, notice period would be 2 months. It was not communicated to me in either format. Its been 2.5 months since I have joined this company but due to work and role mismatch, I have submitted my resignation. I have sent an email to HR and my Director regarding my resignation. After initial discussion, HR told me in a written email that my notice period would be One month. I have communicated the same to my new employer and he agreed for the same. Today I got a call from my current company HR saying that, I looked at your hard copy of your offer letter and now I could see that its 2 months notice. So, they asked me to notify the same to my new employer. But new employer is not ready to hold the offer for 2 months. I am in shock now as my current employer is playing around with my IT career saying that I need to stay back for 2 months. There is a clear policy difference in my soft copy(1 week) vs hard copy(2 months) vs HRs email(1 month). Do I have any right to take up this issue legally ? Since the current employer is in the process of setting up the policies, they are keep changing the policies and always saying that, we need to follow the latest updated policy. Had another conversation with HR just now and he was very rude in the meeting. He said, if you want to go to court, you can always go. He also stated that Hard copy of offer letter(Appointment Letter) will always get the precedence over soft copy of offer letter. Need an advice here as my IT career will impact.