A proposal to extend the Seanad electorate could mean an estimated 5.3 million people entitled to vote, Minister of State Damien English has said.

“There is no doubt about the operational challenges that would be required to deal with numbers of that order, especially given that nearly one-third of the vote could be cast outside the State,’’ he added.

Mr English was responding to the Seanad Bill 2016, moved by Independent Senator Michael McDowell.

The Minister of State said the Bill proposed extending the franchise to all local government electors living in Ireland, persons resident in Northern Ireland who qualified for Irish citizenship and to Irish passport holders born in Ireland living outside the State.

Currently, said Mr English, about 3.3 million people had voting rights and there were a further 1.2 million who could seek them in Northern Ireland. There were about 700,000 passport holders overseas.

He said if they were going to increase the potential Seanad franchise to 5.3 million, as opposed to 162,000, there would be issues to tease out. But the Government was not opposing the Bill, he added.

Mr McDowell said the Bill was drafted by the working group on Seanad reform, chaired by former senator Maurice Manning, to embody the reforms proposed in its report.

“This House can become a forum for voices that have traditionally been marginalised and excluded from the democratic process because of the dynamic of multi-seat proportional representation in our representative politics,’’ he said.

He said there were movements and interests that could never realistically aspire to Dáil seats but should be part of the parliamentary process.