Dear Kanchan,
You could have given little more information. Are you job candidate or HR professionals from the company? Has company issued offer letter to you? When you were expected to join? Has company given in valid reasons for the withdrawal of the offer letter?
Withdrawal of the offer letter is in bad taste. On the strength of the offer letter candidate resigns from the previous company. Withdrawal of offer letter leaves candidate in lurch. Withdrawal candidate in the condition of unemployment, which is nothing but hardship for no fault of candidate.
If you are a candidate then you may approach a lawyer who handles cases for Indian Contract Act, 1872. It is the issue of Appointment Letter, that starts the relationship between the employer and employee. This relationship is a contract between two parties.
Offer letter is nothing but pre-contract agreement. Talk to lawyer and find out whether company can be sued for pre-contract breach.
Thanks,
Dinesh Divekar