The High Court has refused to allow a Belfast student bring a legal challenge aimed at expanding voting rights to Irish citizens in Northern Ireland.

Róisín Morelli had sought leave to seek a judicial review, arguing that Irish citizens in the North had a constitutional right to vote in the May referendum on the Eighth Amendment.

Her lawyers had argued that Irish citizens living in the north would be able to avail of abortion in the same way they can already avail of other health services in the Republic, if the Eighth Amendment is repealed.

They said the refusal to allow Ms Morelli to vote was contrary to the Constitution, the Good Friday Agreement and the European Convention on Human Rights.

However, the High Court refused to grant leave to seek a judicial review and said she did not have an arguable case.

Mr Justice Meenan found it was not open to the Oireachtas to extend the franchise for Dáil and Presidential elections and referendums beyond what is provided for in the Constitution.

If a citizen living outside the Republic was to have a vote in a referendum it would require an amendment to Article 47.6 of the Constitution, the judge said, adding that the case put forward by Ms Morelli in relation to a breach of her constitutional rights fell "well short" of being arguable.

He also said that, while there were references in the Good Friday Agreement to citizenship, there were no provisions concerning voting entitlements and she could not make any case under that agreement.

Judge Meenan also ruled there was no case to argue under the European Convention on Human Rights.

Separately, a former RTÉ journalist was also refused leave to bring a challenge aimed at widening the criteria for postal votes.

Judge Meenan said Michael Fisher did not have an arguable case.

Mr Fisher, who worked for RTÉ for 31 years, will be out of the country on 25 May and wanted permission to bring a challenge aimed at getting the Government to widen the grounds allowing people to cast postal votes.

Judge Meenan ruled that such a move would require a change to existing legislation.

Mr Fisher, who worked for RTÉ in Belfast, now works as a reporter in Co Monaghan.

He said he had "noted the outcome" and would be in further discussion with his legal team about where his case stands.

The judge made no order for costs, meaning all sides in the cases will pay their own.