Top OPEC nations and Russia rejected accusations Friday by US President Donald Trump in a tweet that they were fixing prices.

Despite President Donald Trump's threat Friday that the US will not accept "artificially very high" oil prices, Washington is not expected to take any real action against OPEC or its budding long-term pact with Russia, analysts said Friday.

Crude futures were little changed Friday afternoon, but above session lows, as traders digested a war of words between President Donald Trump and OPEC over oil market conditions.

Surplus crude oil stocks over the five-year average fell to 12 million barrels as of April 1.

Consensus emerging that the current production cut needs to be extended beyond 2018.

"Geopolitical risks are keeping prices supported at the moment," Vishnu Varathan, head of economics and strategy at Mizuho Bank,said.

OPEC and its allies have moved the goalposts on their production cut agreement from rebalancing the market to fostering a more bullish market to incentivize upstream investment.

Western oil majors saw their oil and gas reserves fall for a fourth straight year in 2017 and are replenishing more oil reserves than gas despite an industry trend to rebalance the production mix towards cleaner-burning natural gas.

Total remains committed to its South Pars gas investment in Iran, but the company's CEO said Thursday he is hopeful of obtaining a waiver from the US Administration if it withdraws from the Iran nuclear deal and reimposes sanctions.

The Trump administration has started the regulatory steps to hold at least two lease sales in Alaska's Arctic National Wildlife Refuge in the next decade, as required by the tax bill Congress approved in December.

NYMEX May crude fell 18 cents to settle Thursday at $68.29/b, turning into negative territory when the Omani oil minister was quoted downplaying the likelihood of sharply higher prices.

The 3.5% FOB Rotterdam barge market and Rotterdam 380 CST delivered bunker fuel has hit 3-1/2 year highs in the wake of rising ICE Brent futures.

Bunker fuel demand at West African ports such as Lome and Dakar has been waning over recent months due mainly to high prices, sources said.

The first indications of summer air-conditioning demand emerged Thursday after two vessels were heard on subjects to take fuel oil from Europe for discharge in the Red Sea.

Finnish oil refiner Neste is currently assessing whether or not it will produce 0.5% sulfur bunker fuels for when marine fuel sulfur limits drop to that level in 2020, a company representative told S&P Global Platts Wednesday.

Low sulfur crudes, low sulfur straight run, gasoline and gasoil are some components.

"Scrubbers as a solution [to meet compliance to IMO's 2020 rule] is off the table for now," said Eastport Maritime's Mike Beviss.

Compounding the bullishness, demand has also started to gain momentum, sources said.

Analysts surveyed Monday by S&P Global Platts were looking for US crude stocks to have risen by 625,000 barrels for the same period.

US crude stocks saw a surprise draw last week, while gasoline and distillate inventories both fell by more than was anticipated, data from the Energy Information Administration showed Wednesday.