Czech refinery Ceska Rafinerska AS, majority owned by Unipetrol AS (BAAUNIPE.PR), will shut down for 30 days in the autumn for maintenance, a Unipetrol spokesman said Tuesday.

The shutdown that will start in September and end in October will affect the crude oil refining facilities as well as petrochemical facilities in Litvinov, an industrial town roughly 100 kilometers northwest of
Prague , Borek Konecny told Dow Jones Newswires.

"This is a periodic shutdown that takes place every four years for maintenance and upgrades, it's nothing new," Konecny said.

Shareholders in Ceska Rafinerska are Unipetrol, with a 51% stake, a unit of
Italy 's Eni SpA (ENI.MI) with a 32% stake and a unit of Royal Dutch Shell PLC (RDSA.LN), which holds a 16% stake.

Unipetrol is majority-owned by
Poland 's PKN Orlen SA (PKN.WA).