Traders are also concerned about the slowing down of emerging economies after the US-China war, dampening the demand for fuel.
Benchmark Brent crude fell below $70 a barrel for the first time since early April, down more than 18 percent since reaching four-year highs at the beginning of October.
Mr. Trump has repeatedly has asked oil producers to pump more crude to lower prices.
Oil in NY fell into a bear market, adding pressure on OPEC and its allies to cut production just months after adding barrels.
"Oil prices continue to decline and are now officially in a bear market, having declined 20 per cent from their (October) peak", said William O'Loughlin, investment analyst at Australia's Rivkin Securities.
Gas flares burn from pipes aboard an offshore oil platform in the Persian Gulf's Salman Oil Field, operated by the National Iranian Offshore Oil Co, near Lavan island, Iran. That would mark an abrupt end to six months of supply increases, reflecting the prospect that United States sanctions on Iran won't be deep enough to prevent another surge of American shale oil creating a new surplus.
These sanctions, however, will unlikely cut as much oil out of the market as initially expected as Washington has granted exemptions to Iran's biggest buyers which will allow them to continue buying limited amounts of crude for at least another six months.
Earlier this week, Iraq's oil minister Thamer Ghadhban said the country plans to increase its oil output and export capacity in 2019, with a focus on the southern oilfields, and is close to reaching a deal with worldwide companies.
Al-Falih flew into Baghdad for a meeting with Iraqi Prime Minister Adel Abdul Mahdi ahead of talks between OPEC and its allies in Abu Dhabi Sunday to discuss whether to cut production amid a drop in crude prices.