Sinn Féin and Mary Lou McDonald should confirm that a £1.5 million donation will not be spent by the party in the Republic of Ireland, thereby breaking the law, a Fine Gael Senator has said.

James Reilly said: “Reports in today’s newspapers about the £1.5 million donation to Sinn Féin are of great concern.

“The reporting highlights the intention of the deceased person in their will that the money be left ‘in trust for the political party in the Republic of Ireland known at this time as Sinn Féin.’

“Further reporting notes that the addresses of executors and trustees of the will is the Sinn Féin party headquarters in Dublin.

“Clearly Sinn Féin are not entitled to spend that money in the Republic of Ireland under SIPO rules.

“When Fine Gael came into Government in 2011 we set about cleaning up politics. A big part of this was reducing the amount of money a political party can receive in donations. The Electoral (Amendment) (Political Funding) Act 2012 was the single most significant step in reforming political donations and ensuring transparency, and has broken the old links between big money and politics, ensuring powerful vested interests do not have undue influence over our democracy.

“It is disappointing that Ms McDonald has so far failed to clarify that this money will NOT be spent by Sinn Féin in the Republic of Ireland, and all the more worrying in light of today’s reporting, where we see that was the clear intention of the donation.

“The honourable thing for Sinn Féin to do would be to return the money to the estate, as it cannot be used in this jurisdiction.

“Sinn Féin try to make out they are a legitimate political party and that they have moved on from their days of violence and criminality. If Sinn Féin really want to prove they are a legitimate law-abiding party, then they should certainly abide by the law in this case.

“The only real way to demonstrate that is by returning this donation.”