Oil futures fell 5% on Tuesday, after President Donald Trump said China can continue to buy oil from Iran in the wake of a ceasefire agreement in the Middle East.

Global benchmark Brent fell $3.45, or 4.83%, to $68.03 per barrel. U.S. crude oil was last down $3.37, or 4.92%, to $65.14 per barrel.

"China can now continue to purchase Oil from Iran," Trump said in a post on his social media platform Truth Social. "Hopefully, they will be purchasing plenty from the U.S., also. It was my Great Honor to make this happen!"

Oil prices had added roughly 10% over the mid-June start of Iran-Israel hostilities that were exacerbated in recent days by U.S.' direct military involvement and Iran's retaliatory strike against an American base in Qatar.

Crude futures eased following U.S. President Donald Trump's overnight announcement of an Iran-Israel ceasefire despite lingering questions over implementation and the future of Tehran's nuclear program — the key cause of the recent hostilities cited by Israel and the U.S.

At risk throughout the offensives were supply in both Iran — which produced 3.3 million barrels per day in May, according to OPEC's monthly oil market report released in June, which cites independent analyst sources — and the broader Middle East region, if the conflict spilled over.

Throughout the hostilities, investors also watched whether Iran would proceed with closing the Strait of Hormuz linking the Persian Gulf and the Gulf of Oman — a key route for Iranian and other Middle Eastern shipments, including those of the world's largest crude exporter Saudi Arabia, and the United Arab Emirates, Iraq, Kuwait and Bahrain.

Iran's parliament on Sunday approved the closure of the Strait of Hormuz, according to a report from Iran's state-owned Press TV that CNBC could not independently verify, though a final decision rested with the country's national security council.

"The potential closure of Strait of Hormuz remains a tail risk in our view, but we maintain that oil prices would race past $100/b in such a scenario, due to limited avenues to bypass the narrow passage and the constraints it would pose to the marketability of spare capacity," Barclays analysts said in a Tuesday note, just as Trump announced a tentative ceasefire.

They further added that oil prices came under pressure "as the threat of wider regional conflagration did not materialize despite the US action against Iranian nuclear sites."

Amid risk to supply, the International Energy Agency previously reassured it had 1.2 billion barrels of emergency stockpiles it could resort to. As part of a strategy decided prior to the Iran-Israel escalations, some producers from the influential OPEC+ alliance have also been raising output and have additional spare volumes that could be brought online.