Angolan tycoon Isabel dos Santos, once dubbed "Africa's richest woman", has hit out at the UK for imposing sanctions on her, telling the BBC the move came as a surprise as she had not been found guilty of "any corruption in any court in any country".

Last month, the daughter of Angola's former president was described by the UK government as a "notorious kleptocrat" and slapped with an asset freeze and travel ban for allegedly siphoning wealth out of oil-rich Angola.

She said Angola's government was behind a campaign to tarnish her image.

"It's political at the end of the day," Dos Santos, 51, told the BBC Africa Daily podcast from her base in Dubai.

"There was not an inquiry, where somebody came and investigated and looked at evidence or asked me to clarify. There was no due process," she said.

UK Foreign Secretary David Lammy announced the sanctions on Dos Santos as part of his campaign to crack down on "dirty money".

A government statement alleged she had "systematically abused her positions at state-run companies to embezzle at least £350m [$442m], depriving Angola of resources and funding for much-needed development".

A spokesperson for Angola's attorney-general said it was not a political institution and only investigated evidence of alleged criminality. They said she had been accused of several crimes and so needed to defend herself.

A spokesperson for the British foreign office said that under Global Anti-Corruption Sanctions Regulations, the UK could "designate an individual where there are reasonable grounds to suspect that the individual is or has been involved in serious corruption". They also pointed out that anyone sanctioned could ask for a review at any time.

The allegations against Dos Santos, which she denies, were first made in 2020 when BBC Panorama reported on leaked documents that had been shared with the International Consortium of Investigative Journalists (ICIJ).

The exposé , known as "Luanda Leaks", alleged that one of the most suspicious deals had been made via a London-based company.

Dos Santos, the eldest daughter of former President José Eduardo dos Santos - in power from 1979 to 2017 - was educated at private schools in the UK during Angola's long civil war.

After graduating from King's College London as an electrical engineer, she took up an office job at a consultancy firm in Europe.

But in her early twenties, Dos Santos decided she wanted to pursue a more entrepreneurial career back home, telling the BBC she started out by delivering crates of beer - Uber style - to restaurants and shops.

She went on to build a huge business empire, setting up a mobile phone company, a satellite TV operator, a commercial bank, a brewery and a cement factory - with stakes in other companies in Angola and Portugal.

A month before her 40th birthday, she made it to Forbes magazine's rich list and was not only said to be Africa's richest woman but also the continent's youngest billionaire.

Dos Santos told BBC Africa Daily she never thought of herself in that way but did see herself as a "pioneer".

"I'm also my country's largest private employer. I've created over 200,000 jobs. I've been one of my country's largest taxpayers and contributed the most to build Angola's economy."

In 2016, she was controversially put in charge of the struggling state-owned oil firm, Sonangol. Her appointment was challenged by critics at the time but the Supreme Court stood by it, she said.

"I did have a track record in the private sector. I have a particular knowledge of turning around companies... that are not doing well, to drive them to efficiency."

Some of the most serious allegations of corruption against her date from her time in charge of Sonangol.

Within months of her father stepping down in 2017, she was sacked by his chosen successor, President Joao Lourenço, and two years later her assets were frozen.

The former first daughter of Angola believes Lourenço, who targeted the Dos Santos family as part of an anti-corruption drive, has betrayed her father: "He started blaming the past, saying that everything that happened before him was bad.

"But he himself is from the [ruling] MPLA, he was the vice-president of the party. He was minister of defence.

"If anything, I think he had a lot more to do with the Angolan economy and the Angolan decision-making and the political decision-making than most Angolans."

Dos Santos is also angry that despite her assets being frozen in Angola five years ago, the case has not yet been heard in court - something she says would usually happen within, at most, 18 months as it is a civil case that tends to involve allegations of unpaid debts. She says she faces no criminal proceedings.

She also alleges that the original freezing order was based on faked documents, including a passport in her name bearing the signature of late martial arts expert Bruce Lee.

The spokesperson for Angola's attorney-general said they would not discuss the details of any ongoing legal disputes in public but said that any evidence that documents had been falsified should be presented in court.

By 2021 Forbes had dropped her from its list of top billionaires - Dos Santos explains that the asset freeze means she can no longer get dividend payments and is barred from receiving any financial contributions from her companies.

The mother of three has also had to contend with personal losses over the last few years - her husband died in a diving accident and when her father died in 2022, she did not go back to Angola to attend his funeral.

If she were to return to Angola, she may well face arrest - at the government's behest, Interpol has issued a Red Notice, which is a request to "locate and provisionally arrest" someone, however it is not an international arrest warrant.

Dos Santos says after these difficult years and further asset freezes, she now wants people to hear her side of a "complex" story to "hopefully start clarifying the misconceptions that exist".

When asked if she would ever stand for the presidency, she said it was "a possibility" - echoing comments she made to the BBC four years ago.

"Look, I will always serve my country," she said. "To lead is to serve, and I wish to serve Angola, whether it's in politics, or whether it's in business, whether it's in philanthropy, or culture."