Former Vice President Joe Biden 'not closing the door' on 2020 presidential run "But who knows what the situation is going to be a year and a half from now?"

 -- Former Vice President Joe Biden hasn't made up his mind about whether to run for the Democratic presidential nomination in 2020, but he is "not closing the door," he said today.

"I'm not closing the door. I've been around too long," he said on NBC News' "Today" show. "I'm a great respecter of fate."

Biden added, "But who knows what the situation is going to be a year and a half from now? I don't have any idea."

For now, Biden, 74, wants to focus on Democrats' winning in the midterm elections, he said, as well as his new book, "Promise Me, Dad: A Year of Hope, Hardship and Purpose," a memoir about the last year of his son Beau Biden's life before he succumbed to brain cancer.

Joe Biden announced in 2015 that he would not seek the presidency because the "window on mounting a realistic campaign" closed before his family was able to work through their grief.

"Unfortunately, I believe we're out of time, the time necessary to mount a winning campaign for the nomination," Biden said in October 2015, five months after his son's death.

He does not regret sitting out the race, "because it was the right decision for my family," Biden said in an interview with Oprah Winfrey that aired on Sunday.

Biden, who represented Delaware in the Senate for 36 years, made bids for the White House in 1988 and 2008, when he dropped out and became then-Sen. Barack Obama's running mate. If he chooses to run in 2020, Biden will be 77 on Election Day.

Asked today by NBC News whether his age would be a problem for voters if he mounts a 2020 campaign, Biden said, "I think it's a legitimate issue for people to raise."

"I think people have a right to ask about your age, your health," he added. "I think if anyone were to run for president, you should fully disclose your medical records."

Since leaving the White House, Biden has launched the Biden Foundation the political action committee American Possibilities. He has also been a strong critic of President Donald Trump.

"I do think there's things that [Trump is] doing well," Biden said. "It's more the tone of this administration that bothers me."