China has been the main holdout among the five veto-wielding permanent members of the UN Security Council against slapping a fourth round of sanctions against Iran, arguing instead that more time and attention should be given to diplomacy.
"China will agree to sanctions," Biden told ABC television's "The View" talkshow.
"This is the first time the entire world is unified that Iran is out of bounds… They are more isolated than they've ever been, with their own people and within the region."
The Asian powerhouse has invested heavily in Iran's energy sector and filled the vacuum left by Western firms that have pulled out in the face of US sanctions and political pressure from US allies against companies doing business with Tehran.
Israel and the West accuse Iran of seeking to develop nuclear weapons under the cover of what Tehran insists is an energy program for civilian, not military, purposes.
Biden also assured that Israel, which considers Iran an existential threat, would not attack the Islamic republic without US permission.
"They're not going to do that," Biden said, adding that Israel will first weigh the outcome of diplomatic measures taken by the international community.
"They've agreed the next step is the step we — the president of the United States — has initiated in conjunction with the European powers, the NATO powers, with what they call the P5+1."
The P5+1 groups the five permanent members of the UN Security Council — Britain, China, France, Russia and the United States — plus Germany.
"We're going to continue to keep the pressure on Iran," Biden vowed.
"They are not a monolith," he said about Iran. "They are a fragile government and they're some distance from having that capacity."
He also insisted that President Barack Obama's administration would be successful in preventing Iran from obtaining nuclear weapons.
"The president said our intention is to prevent Iran from getting a nuclear capacity," Biden said. "We believe we'll be able to do that."
The package of new sanctions, already endorsed by Washington's European allies, would include a full arms embargo, a ban on new investments in Iran's energy sector, restrictions on shipping and finance, and sanctions targeting the business interests of Iran's powerful Revolutionary Guards, sources said.
Diplomats say they expect weeks of hard-nosed bargaining before a text — likely to be toned down to make it palatable to the Chinese and the Russians — can be brought to a vote by the full 15-member Security Council.
