Fed Chairwoman Janet Yellen said in an interview with Time Magazine that the Fed's cautious approach in hiking interest rate should help to avoid "the big mistakes". She noted that it was the appropriate approach as there was uncertainty.

"In such an environment, it makes sense to use a risk-management approach to identify and avoid the big mistakes. That's one reason I favour a cautious approach," Yellen said.

The U.S. Energy Information Administration (EIA) released its crude oil inventories data on Wednesday. U.S. crude inventories rose by 6.6 million barrels to 536.5 million in the week to April 08.

Analysts had expected U.S. crude oil inventories to rise by 2.85 million barrels.

Gasoline inventories decreased by 4.2 million barrels, according to the EIA.

Crude stocks at the Cushing, Oklahoma, declined by 1.77 million barrels.

U.S. crude oil imports climbed by 686,000 barrels per day.

Refineries in the U.S. were running at 89.2% of capacity, down from 91.4% the previous week.

The Russian news agency Tass reported on Wednesday that Russia's Energy Minister Alexander Novak said an agreement on the freeze of the oil production could be reached without Iran. He noted that a deal was an open document, adding that everyone could join it.

Novak also said that around 17 countries would participate at the meeting in Doha on April 17.

Saudi Arabia Oil Minister Ali al-Naimi said on Wednesday that the country would not lower its oil production.

Top oil producers will meet in Doha on April to discuss the freeze of the oil output at January levels. Iran will send only a government representative to this meeting.

The Chinese Customs Office released its trade data on Wednesday. China's trade surplus dropped to $29.86 billion in March from $32.59 billion in February, missing expectations for a decline to a surplus of $30.85 billion.

Exports climbed at an annual rate of 11.5% in March, while imports slid at an annual rate of 13.8%, the sixteenth consecutive decline.