Democratic presidential candidate Joe Biden has named leaders for his foreign policy and national security team, while U.S. President Donald Trump tries refute certification of election results in some states.

Biden has announced on Monday that Tony Blinken will be the secretary of state; Jake Sullivan will be the national security adviser; and John Kerry as the climate envoy.

Biden also named Alejandro Mayorkas would become the homeland security secretary. Mayorkas would be the first Latino and migrant to take the position, according to The Guardian report.

Avril Haines would be the director of national intelligence, making her the first woman to be the head of the intelligence agency.

(Photo : Mark Makela/Getty Images)
 President-elect Joe Biden speaks during a virtual meeting with the United States Conference of Mayors on November 23, 2020 in Wilmington, Delaware. As President-elect Biden waits to be approved for official national security briefings, the names of top members of his national security team are being announced to the public. Calls continue for President Trump to concede the election and let the transition proceed without further delay.

Biden also named Linda Thomas-Greenfield to be ambassador to the United Nations. Biden said his choice of cabinet members are equally experienced, innovative, and imaginative when it comes to their jobs.

"Their accomplishments in diplomacy are unmatched, but they also reflect the idea that we cannot meet the profound challenges of this new moment with old thinking and unchanged habits - or without diversity of background and perspective," Biden was quoted in a report.

Biden was also set to appoint Janey Yellen the chair of the U.S. Federal Reserve. This would make Yellen to be the first woman to be seated as the treasury secretary.Yellen is expected to be named as Biden's choice on Tuesday.

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Cabinet Members' Career History

Biden has worked with Blinken before when he was vice president. Blinken was his national security adviser then. He was also deputy secretary of state for two years under former president Barack Obama.

Meanwhile, Sullivan was an adviser to Hillary Clinton, and was known to take part in talks with Iran before the 2015 nuclear deal.

Sullivan then succeeded Blinken as Biden's national security adviser. Kerry is a former senator and Democratic presidential nominee.

Kerry was also Obama's second secretary of state and main creator of Paris climate accord. Trump voted out the United States from the deal during his administration. Thomas-Greenfield's career can be reviewed back to Reagan administration.

She was also known for her service as assistant secretary of state for African affairs under Obama's term.

Obama commends Biden's choices

Meanwhile, Obama lauded Biden's choice of Blinken when he was speaking at Washington Post even to promote his new memoir.

Obama said that Blinken is outstanding and a skilled diplomat, adding that Blinken was regarded around the world and know he is going to do a great job.

Obama, however, said that the previous foreign policy will take time to repair.

"I think it's going to be important to recognise that the confidence that our allies had, and the world had, in American leadership is not going to be restored overnight," Obama was quoted in a report.

While Biden is picking his cabinet members, Trump still refused to concede defeat, and continuously making baseless claims of election fraud.

Trump is blocking Biden's access to financial resources and classified briefings. The president is also calling Republican allies in battleground states to undermine the popular vote.

Trump campaign's lawsuit against the state of Pennsylvania was earlier dismissed by a Pennsylvania judge.

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