U.S. President Donald Trump said ceasefire with Iran is on "massive life support" and rejected Iran's counteroffer as unacceptable.
Iran described its counteroffer as generous, focusing on reopening the Strait of Hormuz, which has been closed for weeks.
Brent crude futures rose 2.0% to $106.30 per barrel, sparking inflation concerns and expectations of central bank rate hikes.
Analysts doubt Trump‑Xi summit in Beijing will break the impasse, noting Trump’s reluctance to militarily escalate.