A loophole in a proposed new law could permit Irish TDs to take seats at the Stormont Assembly while Westminster MPs would be excluded, it has been revealed.
Politicians on the Northern Ireland Affairs Committee have called for the Secretary of State Theresa Villiers to urgently address the issue which they claim could send out strange messages.
During a pre-legislative scrutiny hearing to discuss the Draft Northern Ireland (Miscellaneous Provisions) Bill, which aims to end double jobbing by 2015, Ian Paisley said: "I do not think you get how serious a blunder it would be to create an anomaly where a member of Parliament could not be a member of the Northern Ireland Assembly but a member of a foreign jurisdiction's parliament could sit in the legislative assembly."
The North Antrim MP warned that the loophole could generate great political capital for some parties and would be a source of significant embarrassment. He also told the Secretary of State she would be wise to accept the committee's recommendations on the potentially contentious issue.
He added: "I wonder if it is by accident or design that this anomaly has been created. I hope it is by accident."
In 2010, Sinn Fein president, Gerry Adams resigned as a west Belfast MLA to run for election in the Republic. He was chosen to represent Co Louth in Dil ireann. At the time it was thought TDs were not eligible to sit simultaneously in political establishments on both sides of the border.
Kate Hoey, MP for Vauxhall, said if the new Bill was not amended it would send out a strange message that there is a "special pleading" for members of a foreign country.
Parties in Northern Ireland have strived to end dual mandates after a huge public outcry over double jobbing in recent years. Currently there are just three MPs who take seats at Westminster as well as at Stormont - the DUP's Gregory Campbell and Sammy Wilson DUP as well as SDLP leader Alistair McDonnell. The new legislation means they will have to give up one of their jobs by the end of the Assembly term.
The Bill follows a consultation process which also asked the public about a range of issues. Theresa Villiers said double jobbing between the Northern Ireland Assembly and the Dail did not emerge as a major priority. She added: "I do not see that there is a pressing case to make that change."
The Secretary of State later added: "We are seeking to address concerns that have been made... There is recognition that dual mandates are not appropriate and that concern has not manifested itself in relation to the Dail."