Lawmakers in India are planning to introduce a bill that will ban religious conversion, prompting Christians to express concern that the proposed law will lead to further attacks and persecution targeting them in the mainly Hindu nation.

The legislative proposal, ironically called the "Religious Freedom Bill," seeks to "prohibit conversion from one religion to another by the use of force or allurement or by fraudulent means."

Indian parliamentarians plan to define "force" to include the threat of injury "including threat of divine displeasure."

Under this definition, the bill will outlaw basic Christian doctrines, such as salvation, heaven and hell.

India is the second largest nation in the world, with a population of 1.2 billion next only to China. Of this number, 80.5 percent are followers of Hinduism.

Christians maintain a minority presence in India, with only 2.3 percent or 27 million of the population following the teachings of Jesus Christ.

Paul Robinson, the chief executive of Release International which supports persecuted Christians around the world, warned that the anti-conversion bill may make life more difficult for Christians in India.

"Ultra-nationalists in India are creating a climate of intolerance that will lead to increased religious violence," Robinson said, as quoted on the website of Cross Rhythms.

"This bill would outlaw evangelism and stir up further violence against India's religious minorities," he added.

Robinson further said that the passage of the anti-conversion bill into law will signal the start of "a dark day for human rights" in India.

The American Centre for Law and Justice, a politically conservative Christian-based social activism organisation, meanwhile equated the anti-conversion bill to "radical Hinduism."

The group called on Christians around the world to oppose the proposed law.

"Given the current hostility directed toward Christians in India, we can expect that passage of a national anti-conversion law will lead to a dramatic increase in the persecution of Christians. We must heed the warning of Christians on the ground in India, and oppose the national effort of Hindu extremists to prevent the spreading of the Christian faith," the organisation said in a statement posted on its website.