Oil prices slumped to three-month lows on Monday and the bearish sentiment not expected to shift any time soon thanks to a crisis in Greece, the stocks rout in China and Iran supply fears.
Amrita Sen, chief oil analyst at Energy Aspects consultancy, told CNBC that Brent crude could fall to $55, while U.S. oil prices could weaken to the low-$50s-a-barrel range.
"This is all about the macro picture right now – Greece, the Chinese stock market and the stronger dollar, which are all having a big, big, impact on oil," she said.
Concerns that Greece is fast heading to an exit of the euro zone after voters rejected creditor bailout terms on Sunday and a slump in Chinese stocks have fueled worries about weak demand growth at a time when oil markets have already been hit by a glut of supply.
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Turmoil in China's stock markets has sparked concern that a slowdown in the Chinese economy -- the second largest in the world -- could become more pronounced, reducing demand for oil.