Three months after the Trump administration rejected her, former Nigerian finance minister Ngozi Okonjo-Iweala is set to receive unanimous backing on Monday to become the first woman and first African director-general of the World Trade Organization.

A self-declared "doer" with a track record of taking on seemingly intractable problems, Okonjo-Iweala will have her work cut out for her at the trade body, even with Donald Trump, who had threatened to pull the United States out of the organisation, no longer in the White House.

As director-general, a position that wields limited formal power, Okonjo-Iweala, 66, will need to broker international trade talks in the face of persistent US-China conflict; respond to pressure to reform trade rules; and counter protectionism heightened by the Covid-19 pandemic.

A 25-year veteran of the World Bank, where she oversaw an $81-billion portfolio, Okonjo-Iweala ran against seven other candidates by espousing a belief in trade's ability to lift people out of poverty.

She studied development economics at Harvard after experiencing civil war in Nigeria as a teenager. She returned to the country in 2003 to serve as finance minister and backers point to her hard-nose negotiating skills that helped seal a deal to cancel billions of dollars of Nigerian debt with the Paris Club of creditor nations in 2005.

"She brings stature, she brings experience, a network and a temperament of trying to get things done, which is quite a welcome lot in my view," former WTO chief Pascal Lamy told Reuters. "I think she's a good choice."

Key to her success will be her ability to operate in the centre of a "US-EU-China triangle", he said.

The endorsement of the Biden administration cleared the last obstacle to her appointment.

SWEET BUT STRONG

Okonjo-Iweala becomes one of the few female heads of a major multilateral body. She is expected to join the WTO's Geneva lakeside headquarters within weeks where her portrait is set to be hung beside others of men, mostly white and from rich countries.

Her bright Nigerian prints are sure to stand out among the suits there where the majority of top staff are also men, like most of the delegates and ministers that walk its corridors.

The Trump administration's main criticism of her was that she lacked direct trade experience compared to her main South Korean rival and even supporters say she will have to quickly get up to speed on the technicalities of trade negotiations.

She has rejected this, saying that she has plenty of experience of trade plus other expertise.

"The qualities I have are even better," she said.

Raised by academics, the mother-of-four earned a reputation for hard work and modesty amid the pomp of Nigeria's governing class, acquaintances say.

"She is persistent and stubborn," said Kingsley Moghalu, former deputy governor of Nigeria's central bank who worked with her when she was the country's first female finance minister.

Even when her elderly mother was kidnapped in the Niger Delta, she refused to back down on a series of oil reforms, one of several incidents that earned her the nickname 'Okonjo-Wahala', Wahala meaning "trouble" in Nigerian Pidgin.

"People recognise that this is not someone who is going to tolerate nonsense," her son Uzodinma Iweala, a writer, told Reuters.

"She's a very strong woman like many African woman. There's that song 'Sweet Mother' and that's true for her but you also know that you don't cross a Sweet Mother."

REFORMING THE UNREFORMABLE

The 26-year-old WTO that Okonjo-Iweala inherits after a six-month leadership gap is partially paralysed, thanks to the Trump administration which blocked appointments to its top appeals body that acts as the global arbiter of trade disputes.

But even before Trump, negotiators had struggled to clinch deals that must be agreed by consensus, with the United States and other developed WTO members arguing that developing counties, notably China, cannot cling on to exceptions and that rules need to change to reflect China's economic growth.

Okonjo-Iweala who is a special envoy for the World Health Organization on Covid-19 and, until recently chair of the board of global vaccine alliance Gavi, told Reuters that trade's contribution to public health would be a priority.

The WTO currently faces deadlock over an issue of waiving intellectual property rights for Covid-19 drugs, with many wealthy countries opposed.

High on the to-do list will also be fisheries subsidies, the subject of the WTO's main multilateral talks that missed a deadline to conclude by end-2020.

Asked about the challenges ahead, she joked that a book she wrote about fixing Nigeria's broken institutions could well apply to today's WTO: 'Reforming the Unreformable'.

"I feel I can solve the problems. I'm a known reformer, not someone who talks about it," she said. "I've actually done it".