Former First Minister Alex Salmond has predicted that the hated bedroom tax would lead to the “destruction” of the Liberal Democrats.
The MSP for Aberdeenshire East and Westminster candidate for Gordon claimed the phrase would “haunt” the party.
The spare room subsidy has seen housing benefit slashed by up to 25% where tenants are deemed to have extra rooms.
SNP ministers launched a Scottish Welfare Fund to mitigate the impact of Westminster welfare reforms like the bedroom tax to ensure people were not penalised.
Speaking at a public meeting in An Talla Mòr at Sabhal Mòr Ostaig on Skye, Mr Salmond said: “The Liberals’ pursuit of power with the Tories at Westminster has totally alienated former supporters across Scotland, but nowhere is this more evident than in the west Highlands.
“In these key constituencies the Liberal Democrats are paying the price for their five -year deal with the Conservatives and the two words – bedroom tax – will haunt the Lib Dems to their destruction.
“It was iniquitous across Scotland, forcing people with disabilities into inappropriate accommodation by slashing their housing benefit.
“But in the west Highlands where there was simply no single room accommodation, it was a double iniquity.”
Mr Salmond claimed no one in a rural Scottish constituency would “forgive and forget” political representatives who were prepared to inflict such an injustice on their own constituents.
Ian Blackford is hoping to win the Ross, Skye and Lochaber constituency for the SNP on May 7.
The seat has been represented by former Liberal Democrat leader Charles Kennedy, who is seeking re-election, for nearly 30 years.
A Scottish Lib Dem spokesman said: “As the first minister in the SNP government Mr Salmond centralised local policing, fire and local powers back to Edinburgh.
“Local communities are still feeling the impact of when he took his eye off the ball to focus on his referendum.”
The Lib Dems held 11 seats in the last Westminster parliament but successive opinion polls have suggested the party faces virtual wipe-out at the general election.