Asian shares have skidded following a retreat on Wall Street as the price of crude oil again trades above $100 a barrel

Oil prices extended gains on Wednesday as escalating tensions between the U.S. and Iran fueled concerns over further disruptions to Middle East energy supplies.

Brent crude futures crossed $100 a barrel for the first time since July 24 as escalating U.S.-Iran tensions raised concerns over Middle East oil supplies. With disruptions to…