The historic decision to ban logging in Victoria's old-growth forests has sparked a fresh confrontation between Premier Daniel Andrews and the federal government.

Thousands of timber workers are bracing for job losses and the industry has lashed out at the plan, while conservationists have hailed the protection of thousands of hectares of native forest.

Old growth logging is being phased out. Credit:Paul Rovere

Old-growth forest logging will cease immediately and the harvesting of younger native trees will be phased out completely by 2030, Mr Andrews said in Gippsland on Thursday.

Under the government’s decision, native forest areas the size of Tasmania will be protected by the time the logging ends.