LONDON (Reuters) -Shell's and Equinor's British joint venture, set to become the biggest oil and gas producer in the UK North Sea, will be named Adura, the companies said on Thursday.

The joint venture was formed in December and is expected to increase production from around 140,000 barrels of oil equivalent per day this year, comparable with UK producer Harbour, to over 200,000 boed in the next five years.

Equinor brings tax savings to Adura while Shell's larger oil and gas production offers the venture higher cash flow as it develops new fields, including the Rosebank oil project, which has become a lightning rod for climate activists in Britain.

The name is a combination of Aberdeen, the centre of Britain's oil industry, and the word durability, the companies said.

Shell and Equinor each hold 50% in Adura, which is expected to launch by the end of this year pending regulatory approvals.

(Reporting by Shadia NasrallaEditing by Mark Potter)