Workers on South Africa's Robben Island, where Nelson Mandela was jailed for decades, have gone on strike demanding a 50 percent wage increase.

The workers also want the island, a top tourist attraction, to close for a week during the Christmas season so they can spend more time with their families.

Robben Island Museum chief executive Sibongiseni Mkhize says the museum can not afford to meet the workers' demands nor afford to close during a peak tourist season like Christmas.

He said the island would remain open despite reduced staff, as wage talks continue.

The workers who are on strike run the island's ferries to and from the city of Cape Town, work in the museum shops and sell tickets to tourists.

Mr. Mandela was imprisoned by South Africa's former white minority government for 27 years because of his anti-apartheid activism. He spent many years confined on Robben Island before his release in 1990.

He later served as South Africa's first black president.