US President Joe Biden said Republicans should know that no deal with their party will be made on their terms, during negotiations to raise the public debt ceiling, waiting for the US president to meet with Republican leader in the House of Representatives Kevin McCarthy on Monday to continue negotiations on the thorny file.

Biden has said he is considering the possibility of resorting to a constitutional mechanism that gives him the power to bypass Congress, in order to avoid the country from defaulting on debt, at a time when local media reported that he agreed with McCarthy to meet negotiators of the two parties on the public debt crisis.

McCarthy, who is sticking to demands for spending cuts ahead of any deal with Democrats on the public debt crisis, said he would meet President Biden on Monday to continue negotiations.

The two sides have only 10 days to reach an agreement and allow the United States to continue paying what it owes.

The Republican speaker of the House of Representatives wrote on Twitter after a phone call with the Democratic president: "My position has not changed, Washington cannot continue to spend money that we do not have. We will meet tomorrow (Monday) in person to continue negotiations."

Biden warns

Biden warned in a tweet that he would reject a deal that "protects billions (dollars) in subsidies for big oil companies and jeopardizes the health care of 21 million Americans, or protects the rich from tax fraud and jeopardizes food aid for one million Americans."

In a subsequent tweet during the trip back to Washington from Japan, where he participated in the Group of Seven summit, he stressed that "the United States has never defaulted on its debts, and this will never happen."

In a brief statement later Sunday, McCarthy noted constructive communication between the two sides.

Earlier on Sunday, Biden told reporters at the end of the Group of Seven summit that recent Republican demands for spending cuts as a condition for raising the U.S. government's debt ceiling were "frankly unacceptable."

Article 14 of the Constitution

"Now is the time for the other side to abandon its extremist positions," the US president said, and Biden also indicated that he was considering resorting to a constitutional mechanism to avoid a US default.

"I can't guarantee they won't make them default," he said, adding: "I'm studying Article 14 (of the U.S. Constitution) to see if we have ... legal power," to bypass Congress.

Article 14, which was added to the U.S. Constitution in 1868, states that "the validity of the public debt of the United States permitted by law ... They must not be in doubt", in other words, "expenditures approved by vote must be respected".

For its part, the Treasury Department warned of serious consequences if the cash runs out and the state defaults on its benefits, saying that this will make it unable to pay federal employees and lead to a potential rise in interest rates with spillover effects on companies, mortgages and global markets.

US Treasury Secretary Janet Yellen told NBC on Sunday: "My assessment is that the odds of reaching June 15 and we are able to pay all our bills are very low."

Republicans are demanding that Biden agree to a significant cut in budget expenditures in exchange for agreeing to raise the debt ceiling, while Democrats accuse them of using tactics to advance their political agenda, putting the U.S. economy at risk.

While raising the debt ceiling is usually routine, in recent years it has become a bone of contention with Republican lawmakers seeking spending cuts in exchange for raising the ceiling.

For its part, the Biden administration proposes cutting spending while raising taxes on the richest and companies that benefit from significant tax cuts, but Republicans do not want to raise taxes.

"At this point we have significant differences in terms of revenue," Biden said Sunday.