WASHINGTON, May 15 (Reuters) - U.S. President Joe Biden

and Republican rival Donald Trump on Wednesday accepted an

invitation from CNN to host the candidates' first 2024 debate on

June 27, setting up a high-stakes clash.

"As you said: anywhere, any time, any place," Biden said on

social media after the Democrat for the first time laid out his

terms for taking on the former president on national television.

"President Trump has already accepted the CNN debate

invitation for June 27," Trump's campaign managers said.

But differences between the two sides remained. Biden said

he would participate in two debates, in June and September,

while Trump called for more than two - and a very large venue

"for excitement purposes."

The Democratic president's proposal, the first formal offer

by his campaign, ditched the decades-old tradition of three fall

debates and called for direct negotiations between the Trump and

Biden campaigns over the rules, network hosts and moderators. He

also proposed a separate vice presidential debate in July, after

the Republican National Convention.

A debate is fraught with risks for both candidates, who face

a tight race and low enthusiasm from voters.

Biden's move shows he is willing to take a calculated risk

to boost his opinion poll numbers in a race in which he is

trailing Trump in key battleground states, as voters remain

concerned about his age - 81 - and his handling of the economy.

Trump is 77.

"Make my day, pal," Biden said in a video message. "I'll

even do it twice."

Trump responded to Biden by calling him "the worst debater"

he has ever faced. "I am Ready and Willing to Debate Crooked Joe

at the two proposed times in June and September," he posted.

Trump, who refused to debate his rivals in the Republican

primary race, has in recent weeks been challenging Biden to

engage in a one-on-one matchup with him.

Biden said he would like to debate Trump on the repeal of

the Roe v. Wade decision that guaranteed a national right to

abortion, the threat the former president poses to democracy,

and Trump's economic plans.

Trump told conservative radio host Hugh Hewitt the debate

should be two hours long and that both men should be required to

stand.

Biden's team earlier requested that only broadcast networks

that hosted Republican primary debates in 2016 and Democratic

primary debates in 2020 be eligible to host this year. Only four

networks hosted debates for both parties during those election

cycles: CNN, Telemundo, CBS News and ABC News

.

SHUNNING THE DEBATE COMMISSION

Biden said he would not take part in the traditional

televised showdowns organized by the Commission on Presidential

Debates, rejecting the nonpartisan organization that has managed

presidential debates since 1988.

Trump has also previously expressed interest in bypassing

the commission, and the Republican National Committee announced

in 2022 that the party would leave the commission's debate

system altogether.

In a letter explaining the decision, Biden's campaign chair,

Jennifer O'Malley Dillon, cited the commission's past struggles

to keep candidates from violating the debate rules. She notified

the commission that Biden will not be participating in the three

general-election debates sponsored by the group, which are

scheduled for Sept. 16, Oct. 1 and Oct. 9.

"The debates should be conducted for the benefit of the

American voters, watching on television and at home - not as

entertainment for an in-person audience with raucous or

disruptive partisans and donors, who consume valuable debate

time with noisy spectacles of approval or jeering," she said.

The Biden campaign wants the debates to start much sooner

than the dates proposed by the commission, so voters can see the

two candidates side by side before early voting begins in

September. The first debate would take place after the June 15

conclusion of the Group of Seven summit in Italy and the

conclusion of Trump's criminal trial in New York.

The campaign also wants it to be just the two candidates and

the moderator - without an in-person audience and the

participation of Robert F. Kennedy Jr. or any other independent

or third-party candidates.

Kennedy and the other contenders would not qualify under the

commission's rules given their current rankings in polling and

ballot access.

"They are trying to exclude me from their debate because

they are afraid I would win," Kennedy said on social media.