North Sea oil workers are refusing to work overtime ahead of a series of strikes this week.

Nearly 400 staff on Shell platforms are expected to down tools for 24 hours from 6.30am on Tuesday.

The Unite and RMT union members are unhappy about pay cuts and a switch to a three-week working cycle.

Wood Group staff employed on platforms in the Brent and Central oil and gas fields are refusing to work overtime on Monday ahead of the strike.

Talks held on Friday failed to avert industrial action and no further discussions are expected to be held before the strike begins, the union said.

There will also be a series of  stoppages on Thursday, Friday, Saturday and Sunday.