Two days of planned strike action from members of the Communication Workers Union (CWU) begins today.
Isle of Man Post Office announced late last night it would be going ahead, despite the best efforts from both parties to found a solution to avoid industrial action.
The postal service chief executive, Simon Kneen, says a contingency plan is in place and is apologising to customers in advance for any disruption it may cause.
He added talks between the post office and CWU will continue today.
CWU members voted overwhelmingly in favour of the action earlier this month as a result of an ongoing dispute over proposed pay and pension reforms.
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