It says mail collected on Sundays accounted for 1% of all mail posted but cost four times as much to process as post collected on other days.

Mail had been collected from a sixth of the 118,000 post boxes and 50 business customers since 1990.

The Communication Workers' Union (CWU) opposed the move, which came as its members started to vote on a new deal on pay and conditions following its recent industrial action, the BBC reported.