New Delhi (PTI): The Election Commission has activated its poll machinery across states for a possible roll out of pan-India special intensive revision (SIR) next month just like the one being carried out in Bihar.

The move comes after the Supreme Court last week called the SIR a "constitutional mandate" and permitted the poll panel to continue with the exercise in Bihar.

Several opposition parties and others had moved the top court challenging the intensive revision, saying it will deprive eligible citizens of their right to vote.

Some of the state chief electoral officers have started putting out voters' list published after the last SIR held in their states.

The website of Delhi CEO has the 2008 voters' list when the last intensive revision took place in the national capital. In Uttarakhand, the last SIR took place in 2006 and that year's electoral roll is now on the state CEO website.

The last SIR in states will serve as cut off dates as 2003 voters list of Bihar is being used by EC for intensive revision. Most of the states carried out the revision of electoral rolls between 2002 and 2004.

The poll authority will take a final call on nationwide exercise after July 28 when the Bihar SIR case will come up again for hearing in the top court, an official suggested.

The Election Commission announced that it will eventually carry out an intensive review of electoral rolls across India to remove foreign illegal migrants by checking their place of birth.

Bihar is going to polls this year while assembly polls in these five other states -- Assam, Kerala, Puducherry, Tamil Nadu and West Bengal -- are scheduled in 2026.

The move assumes significance in the wake of a crackdown in various states on illegal foreign migrants, including from Bangladesh and Myanmar.