International oil prices hit a nearly four-year high

London brent crude for November delivery rose 2.7 percent to $80.94 a barrel on Tuesday, its highest since November 12, 2014, before falling back a bit but remaining above $80.Light crude oil for November delivery also rose on the New York mercantile exchange.

Given rising oil prices, US President Donald trump last week called on Opec to increase production to lower crude prices.However, Opec and non-opec producers held their 10th meeting of the joint ministerial supervision committee in Algeria on Wednesday, after which there was no formal announcement on the increase.

The U.S. government pulled out of the comprehensive deal on Iran's nuclear program in May, renewed sanctions on Iran's financial, mineral, automobile and other non-energy sectors in August, and is set to resume sanctions on Iran's energy and other sectors in November.

Iran has the world's fourth-largest oil reserves and is Opec's third-largest producer after Saudi Arabia and Iraq, but production has continued to fall as a result of renewed U.S. sanctions.

Continue to rise

Oil producers are increasingly reluctant to increase output and the market will face a supply gap in the next three to six months, pushing prices higher, BNP paribas crude analyst harry chilanghelian told Reuters.

Futures trader toback ltd. and Swiss energy trader mercuria energy group made similar forecasts Thursday.They speculated that the price of brent crude would rise to $90 a barrel by Christmas this year and above $100 in early 2019 as U.S. energy sanctions on Iran resumed in November.

J.p. Morgan chase & Co. forecast that U.S. sanctions will lead to a further decline in Iranian crude oil production, which could drop by 1.5 million barrels a day.

Iran produced 2.06 million BPD of crude oil per day in August, down sharply from 3.09 million BPD in April, according to the latest data from Thomson Reuters Eikon.

Iran has previously said that Mr Trump was "wrong" and that countries such as Saudi Arabia were unable to fill the gap in crude supplies caused by Iran being "blocked".

Some analysts have speculated that higher oil prices for U.S. consumers, which are set for November's midterm congressional elections, will be a "headache" for trump.