Three of the country's four main parties have experienced a drop in support.

According to the latest opinion poll Fine Gael, Labour and Fianna Fáil have recorded a slump in popularity - while Sinn Féin is on the up.

The Sunday Independent, Millward Brown survey shows Fine Gael is down 3 points to 27 per cent.

Labour is down 4 points to 8 per cent and Fianna Fáil drops 5 points to 21. 

That puts them behind Sinn Féin who go up 6 to 22 - their highest level of support since the General Election. 

Greens and others also go up 6 to 21 per cent. 

Fionnan Sheahan, Group Political Editor for the Sunday Independent, explains the reason behind the changes: