New Delhi, Aug. 24 -- Iran's oil shipments to Asian buyers have nearly dried up, pushing the price of Iranian crude to its highest levels in years as US prepares to announce fresh measures aimed at isolating Tehran and those trading with it.

China's private refiners, which have traditionally been the biggest buyers of Iranian oil, are now facing tighter supplies. Iranian crude that was previously sold at a discount to global benchmarks is being offered at a premium of about $4 a barrel, Bloomberg reported.

The traders, cited by the Bloomberg, who asked not to be identified because the discussions are private, said the supply squeeze has intensified in recent weeks.

A major factor behind the shortage is the impact of US efforts to block...