Fianna Fáil has opened up a strong lead on Fine Gael as the country’s most popular political party according to the latest behaviour and attitudes poll.

It marks the end of a miserable week for the government following the fallout from the garda whistleblower controversy.

The Sunday Times poll was taken over a nine-day period leading up to Wednesday - just as the extent of the scandal was breaking.

The poll shows Fianna Fail up three points to 32% with Fine Gael dropping two points to 21%.

Sinn Féin have risen two points to 19%.

Fianna Fáil’s 11 point lead is the largest the party has ever held in the six years the poll has been running.

The results are made all the more significant following Sinn Féin’s announcement that it will next week table a motion of no confidence in the government.

The party is basing the motion on the government’s handling of the Maurice McCabe affair and the crisis in the health service.

Fianna Fáil's confidence and supply arrangement with the government requires it either to abstain or vote against the motion - however the possibility of fresh elections may look more appealing following the positive poll results emerging tonight.

Earlier, Fianna Fáil's spokesperson on Foreign Affairs and Trade Darragh O'Brien rejected Sinn Féin's call for the party to withdraw its support for Fine Gael and said collapsing the government would not provide any answers to the ongoing whistleblower scandal.

The motion of no confidence debate - likely to take place on Wednesday with a vote the following day - now represents a major test of Fianna Fáil’s commitment to keeping the current government in place.