Joe Biden has said he is “not blind” to concerns about his age but has told critics it is “time to end” speculation about his future in the US presidential race.

In a letter to Democrats in Congress, the US president said he was “firmly committed” to his re-election campaign and vowed to remain in the contest against Donald Trump.

“I want you to know that despite all the speculation in the press and elsewhere, I am firmly committed to staying in this race, to running this race to the end, and to beating Donald Trump,” Mr Biden wrote.

Around the same time the letter was published, the US president phoned in to MSNBC’s Morning Joe program and said he is confident the “average voter out there” still wants him on the Democrat ticket.

Mr Biden said: “I am not going anywhere.”

He added that losing is “not an option” in the upcoming election and that he hasn’t “lost to Trump”.

Mr Biden also told MSNBC he is not going to “explain any more about what I should or shouldn’t do”, saying: “I am running.”

The US president added that he is “frustrated” by calls from party officials for him to step aside.

“They’re big names, but I don’t care what those big names think,” Mr Biden said.

He also said those in the party who are calling for him to quit should “challenge me at the convention”.

The Democratic National Convention in August is when delegates will officially select the party’s presidential and vice presidential nominees.

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‘I’m not going anywhere’

There have been concerns about the health and capability of the 81-year-old president after a shaky performance in a debate with Trump last month.

Democrats described Mr Biden’s performance as an “unmitigated disaster”, “a meltdown”, and “a slow-motion car crash”.

Even some of Mr Biden’s closest political allies, including the former speaker of the US House of Representatives Nancy Pelosi, have raised questions about his health.

In his letter today, Mr Biden writes that he has had “extensive conversations” with the leadership of the Democrat party and “most importantly, Democratic voters” over the past 10 days.

He continues: “I have heard the concerns that people have – their good faith fears and worries about what is at stake in this election.

“I am not blind to them.”

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In relation to the concerns raised about his health and suitability to run, Mr Biden adds: “I can respond to all this by saying clearly and unequivocally: I wouldn’t be running again if I did not absolutely believe I was the best person to beat Donald Trump in 2024.”

The US president says that he was voted to be the Democratic presidential candidate by a “wide margin”, adding: “How can we stand for democracy in our nation if we ignore it in our party?”

Mr Biden claims his record as president will help him secure re-election to the White House, and says his party has an “economic vision to run on that soundly beats Trump and the MAGA Republicans”.

Read more:
Biden addresses speculation over his future
Trump claims Biden is quitting election
Biden says he ‘nearly fell asleep’ during TV debate

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The US president ends his letter by saying: “The question of how to move forward has been well-aired for over a week now. And it’s time for it to end.

“We have one job. And that is to beat Donald Trump… any weakening of resolve or lack of clarity about the task ahead only helps Trump and hurts us.

“It is time to come together, move forward as a unified party, and defeat Donald Trump.”

The letter comes days after Mr Biden vowed I am “staying in the race” at a rally in the key battleground state of Wisconsin.

As he spoke, the Washington Post reported Democratic Senator Mark Warner was trying to assemble a group to ask Mr Biden to step aside, citing two sources close to the effort.

Sky’s US partner NBC News reported that Senator Warner has been focussing on a path forward for Mr Biden, rather than a definitive effort to oust him.