Her term is scheduled to start on March 1.
The World Trade Organization officially named USA -trained Nigerian economist Ngozi Okonjo-Iweala as its seventh director-general on Monday.
Okonjo-Iweala is the first African official and the first woman to hold the job.
In response to concerns that rich countries are not doing enough to share vaccines, Okonjo-Iweala said that the WTO needs "rules that will allow access and equity for vaccines, and therapeutics and diagnostics".
She also expressed willingness to make the WTO stronger, adding that the organisation would adapt to realities of the day.
The post of the top executive has been vacant since August 31 past year, when the former head of the organisation, Roberto Azevedo, left it before the end of his term. Her predecessor, Roberto Azevedo, stepped down August 31, a year before his term expired.
The minority leader said that the election was clearly in recognition of Okonjo-Iweala's competence.Elumelu said that the caucus commended the understanding and spirit of sportsmanship exhibited by the South Korean Trade Minister, Yoo Myung-hee, in withdrawing from the race.He said it was another loud testament to Okonjo-Iweala's suitability for the task ahead.
Okonjo-Iweala said she was "honoured" to be selected to lead the organization, and vowed to take on global economic and health challenges brought on by the coronavirus pandemic.
"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 last week.
Okonjo-Iweala, an economist whose background is in global development, rose to become managing director of the World Bank.
The Nigerian, who boasted US, EU and African backing, celebrated her appointment with her sister, at her home outside Washington.
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, can not cling on to exceptions and that rules need to change to reflect China's economic growth.
There is also a fragile issue of determining whether the USA broke WTO rules when the Trump administration, citing national security concerns, unilaterally boosted tariffs on steel and aluminum in 2018, Politico reports.
European Union chief Ursula von der Leyen called it a "historic moment for the entire world", and pledged Europe's full backing for Okonjo-Iweala.
Amb. Walker extended his thanks to all eight of the candidates who participated in the selection process and particularly to Ms Yoo "for her ongoing commitment to and support for the multilateral trading system and for the WTO". It negotiates and administers rules for global trade and tries to resolve disputes among its 164 members.
Twice Nigeria's finance minister (2003-2006 and 2011-2015) and its first female foreign minister in a two-month stint in 2006, Okonjo-Iweala is seen as a trailblazer in her homeland.
A development economist by training with degrees from the Massachusetts Institute of Technology and Harvard, Okonjo-Iweala has also had a 25-year career as a development economist at the World Bank, eventually becoming its number two. "So, this is an area of work", she said.
Okonjo-Iweala has brushed off claims she lacks experience as a trade minister or negotiator, putting the emphasis on her drive. "Her strong will and determination will drive her to tirelessly promote free trade to the benefit of people worldwide".