SINGAPORE--Oil held above $70 in Asia Wednesday after volatile trade overnight sparked by a weakening US dollar and political unrest in key crude producers Iran and Nigeria.

New York's main futures contract, light sweet crude for delivery in July, eased 13 cents to $70.34 a barrel.

Brent North Sea crude for August delivery dipped seven cents to $70.17.

Prices eased due to "continued demand concerns and concerns that the market went up too high, too fast," said Bart Melek of BMO Capital Markets.

Crude soared more than two dollars to $72.77 a barrel on Tuesday on a weakening greenback and indications of a US housing recovery, but retreated as traders realized the rally had been overdone.

The market was also reacting to developments in crude producers Iran and Nigeria, another analyst said.

"Political unrest following the presidential elections in Iran and bombing attacks on oil plants in Nigeria represent an explosive mix for the oil market," said Commerzbank commodities analyst Eugen Weinberg.

Iran's election watchdog said Tuesday it was ready for a recount in the disputed presidential vote as the nation braced for further protests after at least seven people were killed in street battles, according to state media.

The Islamic republic is the second biggest crude oil producer in the Organization of the Petroleum Exporting Countries (OPEC), after Saudi Arabia.

Meanwhile, tensions remained high in Nigeria after militants in the Niger Delta claimed attacks against facilities run by US oil giant Chevron.

The Movement for the Emancipation of the Niger Delta (MEND) also threatened to extend its operations beyond Delta State to others in the oil-rich but volatile southern region.