The Irish government will push Northern Ireland's political parties to make a fresh attempt at restoring their devolved power-sharing government later this year, Prime Minister Leo Varadkar said on Tuesday.

"We would intend in the autumn some time trying again to get the parties in Northern Ireland together," Varadkar told a news conference after the latest attempt to end a more than 18-month deadlock failed earlier this year.

"I think the absence of any clarity around Brexit makes that very difficult but if we can have that in October, I think there is an opportunity certainly before the end of the year to get the assembly and executive up and running."