SAN FRANCISCO -- Volkswagen Group argued in a court filing that fines sought by the U.S. government to penalize the automaker for rigging diesel vehicles to cheat emissions test are excessive.

Volkswagen said in the filing Tuesday in San Francisco federal court that it remains fully committed to settling the government's claims. It said it was presenting its response because the government's probe is continuing.

The filing follows a brief court appearance earlier Tuesday in which the judge overseeing government and consumer lawsuits against Volkswagen said that lawyers were "on pace" to meet a June 21 deadline for submitting a proposal to fix 480,000 manipulated vehicles in the U.S. or get them off the road.

U.S. District Judge Charles Breyer said that buybacks, cash compensation for consumers and a fund to address damages from the excess emissions and future research must be part of any settlement. The deal to resolve civil claims over cars rigged to cheat pollution rules is said to be worth about $10 billion.