Saturday's resolution, which followed a meeting in the central city of Raipur by the Bharatiya Janata Party is likely to exacerbate Hindu-Muslim tensions.
The resolution, however, also said a parliamentary law to sanction the construction would need the support of allies and the opposition Congress party.
The Hindu nationalists appear to be trying to persuade both hardliners demanding the construction of the temple and moderates who do not want to isolate or alienate India's 135 million Muslims ahead of national elections.
Assembly elections are scheduled for November in five states, and national polls are due next year.
In recent weeks, Hindu hardliners have been demanding that the BJP pass a law which will hand over the disputed plot of land claimed by both Hindus and Muslims.
The dispute centres around the ruins of the 16th century Babri mosque in the northern Indian state of Ayodhya.
It was demolished in 1992 in a campaign led by the BJP, leading to the worst violence between the two communities in decades. More than 2,000 people were killed.
In preliminary findings released in June, the Archaeological Survey of India said it had found no evidence from a dig at the site that it ever held a Hindu temple.