A class-action suit against California's Anthem Blue Cross was filed by consumer advocates on Monday, accusing the largest for-profit health insurer across the state of illegally using unexpected and high rate hikes to try and force customers into inferior health plans.

The suit has come a mere two days before top level executives from various major US health insurance companies, including WellPoint, Anthem's parent firm, are to meet in Washington with the Obama Administration officials to discuss the rising premium rates.

The lawsuit filed in California stresses that Anthem violated state law by closing certain blocks of its individual health plans to new members, without offering any comparable coverage to policyholders who preferred to remain.

Anthem's plans to boost its premiums by as much as 39% has managed to stir much controversy. The company has been, in addition to bitter criticism, the target of inquiries by state regulators and congressional committees.