The Caribbean island nation of Barbados will tonight sever centuries-old ties to the British monarchy, ditching Queen Elizabeth II as head of state and declaring itself the world's newest republic.

The Royal Standard flag that represents the queen will be lowered in the capital Bridgetown and - at midnight (4am Irish time) - the current governor-general, Sandra Mason, will be inaugurated as the first president.

Prince Charles, heir to the British throne, will attend the 'Pride of Nationhood' ceremony, which is set to include military parades, a mounted guard of honour, gun salutes, dances and fireworks.

The new era for Barbados has fuelled debate among the population of 285,000 over colonialism and Britain's centuries of influence, including more than 200 years of slavery until 1834.

Prince Charles is greeted by Sandra Mason as he arrives at Bridgetown Airport in Barbados
Prince Charles is greeted by Sandra Mason as he arrives at Bridgetown Airport in Barbados

And Prince Charles' visit was clouded at the last minute by another race row over alleged comments about his grandson.

Charles' youngest son Prince Harry and his wife Meghan - who has a black mother and a white father - have said an unnamed royal asked how dark their unborn first child's skin would be.

After a new book reportedly claimed that Charles was responsible, his spokesman said that "this is fiction and not worth further comment".

Barbados, famous for its idyllic beaches and as the birthplace of singer Rihanna, won independence from Britain in 1966.

In October, it elected Ms Mason to become its first president, one year after Prime Minister Mia Mottley declared the country would "fully" leave behind its colonial past.

British officials said Charles would use his speech in Barbados to stress continuing ties between the two countries, including through the Commonwealth group of nations.

But local criticism has focused on Ms Mottley (below) inviting Charles to be the guest of honour, and to award him the Order of Freedom of Barbados, the highest national honour.

Mia Mottley

Some Barbadians argue there are more pressing national issues than replacing the queen, including economic turmoil caused by the Covid-19 pandemic that has exposed overreliance on tourism - which, ironically, is dependent on British visitors.

Eerie calm in usually bustling Bridgetown, paltry numbers at popular tourist spots and a dead nightlife scene all point to a country struggling after years of relative prosperity.

Unemployment is at nearly 16%, up from 9% in recent years, and the country has just eased a longstanding Covid-19 curfew, pushing it back from 9pm to midnight.

Opposition leader Bishop Joseph Atherley said the celebrations among dignitaries would largely not be accessible to ordinary people.

"I just don't think we are doing ourselves a credit and a just service by having this when people are being admonished to sit in the comfort of your home and watch on a screen," Mr Atherley said.

Buoyed by Black Lives Matter movements across the world, local activists last year successfully advocated for the removal of a statue of the British Admiral Lord Horatio Nelson that stood in National Heroes Square for two centuries.

And the end of the queen's reign is seen by some as a necessary step towards financial reparations to address the historic consequences of the use of slaves brought from Africa to work on sugar plantations.

For many Barbadians, replacing the British queen is just catching up with how the nation has felt for many years.

"The symbolism of being able to aspire to become head of state is so powerful," Prime Minister Mottley said last week.

"Our president-elect, who will be sworn in on Monday night... is the person who will bring immense pride to every Barbadian boy and girl."