The Indian government has considerably eased the restrictions relating to investments by NRIs in house property. There is virtually no restriction or approval required for an NRI to invest in properties in India from funds received in India through normal banking channels or held in Non-Resident External (NRE) account/ Foreign Currency Non-Resident (FCNR) account (B)/ Non-Resident Ordinary (NRO) rupee account.
However, investment in agricultural land / plantation property / farm house is currently prohibited. The recurring rental income earned on letting out of property is also freely repatriable.
For a detailed overview of an overview of the key exchange control and tax implications that should be considered by NRIs while investing in house property in India check this out