ASTANA, Nov 21 (Reuters) - Kazakhstan's giant Kashagan oil field has started commercial output, the Central Asian nation's energy minister said on Monday, a milestone for the repeatedly delayed $55 billion project.

The offshore field has produced about 0.5 million tonnes (3.8 million barrels) of oil since test pumping began on Sept. 28, Kanat Bozumbayev told parliament, and daily output has exceeded 75,000 barrels since Nov.1.

The former Soviet republic expects Kashagan to produce up to 1.1 million tonnes of oil this year and 4.0-8.0 million tonnes next year, helping it offset natural output decline at many mature fields.

The field off Kazakhstan's Caspian coast has cost about $55 billion to develop, according to analyst estimates. It first started production in 2013 but output was suspended shortly afterwards due to of technical problems with the gas pipelines.

The NCOC consortium developing Kashagan comprises China National Petroleum Corp (CNPET.UL) , Exxon Mobil (XOM.N) , Eni (ENI.MI) , Royal Dutch Shell (RDSa.L) , Total (TOTF.PA) , Inpex (1605.T) and KazMunaiGas (KMGZ.KZ) .