The Palace said King Charles takes the issue "profoundly seriously".

The research is being carried out by the University of Manchester with Historic Royal Palaces.

Buckingham Palace is granting researchers full access to the Royal Archives and the Royal Collection.

The study, a PhD project by historian Camilla de Koning, is expected to be completed in 2026.

Both the King and the Prince of Wales have previously expressed their personal sorrow at the suffering caused by the slave trade.

Speaking during a trip to Rwanda last year, the King said he could not describe "the depths of his personal sorrow" at the suffering caused by the slave trade.

In a visit to Jamaica last spring, Prince William said slavery was abhorrent, "should never have happened" and "forever stains our history".

The King wants to continue his pledge to deepen his understanding of slavery's impact with "vigour and determination" since his accession, a Buckingham Palace spokesperson said.

They continued: "This is an issue that His Majesty takes profoundly seriously."

"Given the complexities of the issues it is important to explore them as thoroughly as possible."

A Palace statement was issued in response to the Guardian, which has published a previously unseen document showing the 1689 transfer of shares in the slave-trading Royal African Company from Edward Colston - the slave trader and the company's deputy governor - to King William III.

The King has also said that each Commonwealth country should make its own decision over whether it is a constitutional monarchy or a republic.

He said he was aware the roots of the Commonwealth organisation "run deep into the most painful period of our history" and said acknowledging the wrongs of the past was a "conversation whose time has come".

There are currently 14 Commonwealth Realms in addition to the UK where the King is their head of state.

Dr Halima Begum, chief executive of the Runnymede Trust - a race equality think tank - told the BBC "it is wonderful to see King Charles building on his mother's legacy".

She described it as "incredibly encouraging" to see an incremental engagement from the monarchy on issues surrounding the injustice of slavery.

Dr Begum went on to say that the "next step could be a royal commission to unearth the complex histories of colonialism," and that it would "really inspire millions of British citizens, and of course citizens across the Commonwealth".

The Palace's announcement came as the King took part in a centuries-old Easter tradition, known as Maundy Thursday, for the first time since becoming monarch.

PhD student Ms de Koning said "the royals are often overlooked when it comes to influence".

She told BBC Radio 4's World at One programme: "It seems like they are just stamping decrees, but they are actually very involved as diplomatic players.

"I'm hoping to change that perspective, that you can see there are way more links between the colonial and the monarch than ever have been investigated, or have ever been noticed, so we can flip that around."

Dr Edmond Smith, who is supervising Ms de Koning's project, said the crown has "often been left out of discussions" on the transatlantic slave trade, calling it an "important hole that needed to be filled through the research".

"How the royal household may take that research on board is something we can only hope to see develop in the coming years," he added.

The PhD study is co-sponsored by Historic Royal Palaces which manages several sites.

It started in October, one month after the King came to the throne.

It will look into the extent of any investments from any other slave trading companies.