The Yukon's social assistance rates are too low and need a major overhaul, Liberal leader Arthur Mitchell says.

Echoing concerns raised during the recent territorial election, Mitchell told the legislature Monday the rates have not been increased since 1991.

"There was a supplementary budget that revealed the government is sitting on some $85 million in net financial resources, thanks to massive transfers of money from the government of Canada, yet there was no money indicated for social assistance increases," Mitchell said.

Social assistance pays an average of $390 per month for rent while the average rent in Whitehorse is $675, he said.

The $160 monthly payment for food is also insufficient, he said.

Social Services Minister Brad Cathers defended the rates, saying they are among the highest in Canada.

"Certainly I recognize that social assistance can be a challenge for people to live on," Cathers said. "We want to be sure in structuring the system that it fulfils its role as a safety net. It is intended to be adequate and we're committed to making sure that it does so." 

The government is reviewing the rates but there is no deadline for the final report, he said.