Bernie Sanders is feeling determined and views beating Donald Trump as “very important”, his brother has said as his sibling confirmed he will run for US president in 2020.
The left-wing Vermont senator announced his plans to seek the Democrat nomination for a second time on Tuesday.
Mr Sanders, 77, lost out in the race to become the Democrats’ US presidential election nominee to Hillary Clinton in 2016, despite garnering more than 13 million votes during the primaries.
Gaining international recognition, his bid became known as a movement that inspired and galvanised a generation, and has seen him credited with changing American politics.
Speaking to the Press Association, his brother Larry, who lives in Oxford, said his younger sibling is feeling “determined”, perhaps in some ways more than ever.
Of his brother’s decision to return as a Democrat contender, the 83-year-old said: “He did ask me, I think for the first time in his life, what I thought about this a couple of months ago.
“I said, ‘as your brother I think you shouldn’t do it because you could have a marvellous life, but as a world citizen you have to’. That’s my opinion.”
Moving to Britain from his native Brooklyn, New York, in the 1960s, Larry said Mr Sanders continues to work “flat out all the time”, and that he does not know how his brother manages.
He also revealed that his sibling, whom he calls Bernard, thinks the Trump administration is a “disaster for the world”, adding: “I think the need to beat Trump is very important to him.”
Larry said he predicts the Democrat nomination race will be a “rerun between the mainstream Democrats, who are still very powerful, and the progressive Democrats”.
With Mr Sanders likely to speak for the progressives, he said his brother will be against whoever the mainstream Democrats back, with California senator Kamala Harris the current favourite.
“If he wins the nomination, he will certainly beat Trump. The nomination is the harder part,” Larry added.
Some of Mr Sanders’s policies have previously included breaking up the big banks, creating more jobs for youngsters, a single-payer national health care programme and free university tuition fees.
Larry, who is active in British politics and the Green Party spokesman on health and social care, said there will be “no surprises” when it comes to Mr Sanders’s policies in this presidential campaign.
Mr Sanders has described his new White House bid as a “continuation of what we did in 2016”, and how many of the policies he advocated three years ago are now embraced by the Democrats.
In an email to supporters, Mr Sanders said his campaign is “not only about defeating Donald Trump”, adding that is about transforming the country and creating a “government based on the principles of economic, social, racial and environmental justice”.
Asked how likely it is that Mr Sanders could secure the Democrat nomination, Larry, a former Oxford University lecturer, revealed he is in favour of his brother 60/40.
“He came fairly close last time and he is much more known, and his policies are much better understood now, so I think that will tip it,” he added.
Despite the expanse of the Atlantic Ocean separating them for the best part of more than five decades, Larry has previously said he and his brother are still close, often speaking on a bi-weekly basis.
Quizzed on how proud he is of his younger sibling, Larry said “very”.
“What he has done, I don’t think anyone has done it, even as getting as far as this in shifting American politics, and by shifting American politics it has a world impact,” he said.
“His great goal has never been to win for himself, his great goal has always been to change politics and he will carry on doing that.”