His comments come at a time when energy market participants expect USA sanctions on crisis-stricken Venezuela, as well as OPEC-led production cuts, to offset a potential supply glut this year.
Benchmark Brent crude had slipped 62 cents to $61.36 a barrel by 1000 GMT, after rallying about 15 percent in January.
USA crude inventories rose by 2.5 million barrels last week and gasoline stocks also increased, the American Petroleum Institute said.
Another factor behind the oil market rally is the supply cuts imposed by the member-states of the Organization of the Petroleum Exporting Countries (OPEC) and allied oil producers. Stocks gained by 1.3 million barrels in the week ended February 1, compared with analysts' expectations for an increase of 2.2 million barrels. They also expect that gasoline and distillate inventories each posted gains of 1.7 million barrels.
The producers known as OPEC+ started cutting production by 1.2 million barrels per day (bpd) from last month to avert a new supply glut, and OPEC has delivered nearly three-quarters of its pledged cuts already, a Reuters survey showed last week. "Because the number was a little disappointing, it played into the slowing demand scenario", said Phil Flynn, oil analyst at Price Futures Group in Chicago. The sanctions aim to block USA refiners from paying into PDVSA accounts controlled by Venezuelan President Nicolas Maduro.
A flotilla loaded with about seven million barrels of Venezuelan oil has formed in the Gulf of Mexico, some holding cargoes bought ahead of the latest US sanctions and others whose buyers are weighing whom to pay, according to traders, shippers and Refinitiv Eikon data.
Late last month, the USA imposed sweeping sanctions on oil firm PDVSA.
When asked about how European and Asian customers could be convinced to buy oil from Venezuela, risking sanctions from Washington, he stated that now, Washington's sanctions apply only to USA entities.
"Despite several forays in WTI above our prior resistance of $55, the market continues to draft back down largely under the pressure of this week's stronger dollar", Jim Ritterbusch, president of Ritterbusch and Associates, said in a note.
OPEC oil supply fell in January by the largest amount in two years despite sluggish production declines from Russian Federation, according to a Reuters survey.
U.S. President Donald Trump last week said he would meet his Chinese counterpart Xi Jinping in coming weeks to try to settle the two countries' dispute.