By Vladimir Soldatkin, Alex Lawler and Rania El Gamal
MOSCOW/LONDON/DUBAI (Reuters) - Top oil nations struggled to finalise record output cuts at G20 talks on Friday to boost prices slammed by the coronavirus crisis, as Saudi Arabia clashed with Mexico despite U.S. President Donald Trump's mediation offer.
OPEC led by Saudi Arabia and its allies led by Russia, which together make up the informal OPEC+ group, had forged a pact to curb crude production by 10 million barrels per day (bpd) or 10% of global supplies in marathon talks on Thursday.
Russia and OPEC said they wanted other producers including the United States and Canada to cut a further 5%.
But efforts to conclude the deal hit the buffers when Mexico said it would only cut output by a quarter of the amount demanded by OPEC+.
Measures to curb the spread of the coronavirus have destroyed demand for fuel and driven down oil prices, straining budgets of oil producers and hammering the U.S. shale industry which is more vulnerable to low prices due to its higher costs.
Mexico President Andres Manuel Lopez Obrador said on Friday Trump had offered to make extra U.S. cuts on his behalf, an unusual offer by a president who has long railed against OPEC.
Trump, who had threatened Saudi Arabia with oil tariffs if it did not fix the market's oversupply problem, said Washington would help Mexico by picking up "some of the slack" and being reimbursed later. He did not say how this would work.
But the offer was still not enough to close the deal.
Two sources familiar with the discussions said Saudi Arabia clashed with Mexico on Thursday and again on Friday, when the kingdom hosted talks of energy ministers from the Group of 20 major economies that were aimed at endorsing OPEC+ efforts.
Hours after talks ended, a G20 communique made no mention of the cuts or quantities, but only referred to "measures to ensure energy market stability". It remained unclear how the OPEC+ pact could be now finalised.
"We call on all nations to use every means at their disposal to help reduce the surplus," U.S. Energy Secretary Dan Brouillette had told the G20 talks.
Brouillette said the United States would offer supporty with a natural decline in its oil output driven by economic forces. Although not a formal cut, it still represents a major shift for by a country which has never joined OPEC in coordinated action.
Brouillette said U.S. output could fall by between 2 million and 3 million bpd by the end of 2020 - a bigger drop over a shorter period of time than officials previously indicated.
Crude oil prices vs U.S. crude oil stocks https://fingfx.thomsonreuters.com/gfx/ce/dgkplangvbx/CrudevsOilStocks.png
Kremlin spokesman Dmitry Peskov said action involving others was "unavoidable", even though he acknowledged U.S. law barred American producers from joining any price cartel.
Trump and Russian President Vladimir Putin held talks on Friday that included discussing the energy market.
Oil markets were closed on Friday but prices failed to rally after Thursday's talks on cuts, because even an unprecedented cut of 15% in global supplies, as envisaged by OPEC+, would still leave a huge overhang when demand has plunged 30%.
The Mexican president said Mexico offered OPEC+ a cut of just 100,000 bpd, not the 400,000 bpd demanded, but said Trump had "very generously said to me that they were going to help us with the additional 250,000 (bpd)" of cuts.
Mexico, which has long been in a standoff with Washington over Trump's plan to build a wall between the two countries, cares less about low oil prices and more about volume because of its hedging programme, which protects it against price falls.
The crisis in the oil market has pushed Russia and Saudi Arabia to patch up differences after their acrimonious OPEC+ meeting in March where a dispute over how best to tackle falling prices led them to scrap their existing pact on production restraint that had helped balance the market for three years.
The new OPEC+ deal envisaged all members reducing output by 23%, with Saudi Arabia and Russia each cutting 2.5 million bpd and Iraq cutting over 1 million bpd in May and June.
Riyadh and Moscow agreed that their cuts would both be calculated from an October 2018 baseline of 11 million bpd, even though Saudi supplies surged to 12.3 million bpd this April.
Under the plans, OPEC+ would ease cuts to 8 million bpd from July to December and relax them further to 6 million bpd between January 2021 and April 2022, OPEC+ documents showed.
Norway and Canada, both outside OPEC+, have suggested they could cut if the deal was implemented.
UBS said the cuts were still not enough. "We still see Brent falling to $20 per barrel or lower in the second quarter of 2020," it said.
OPEC+ 10 million bpd cut distribution for May-June https://fingfx.thomsonreuters.com/gfx/ce/xegvbqrgpqz/OPEC10mlncut.PNG
(Additional reporting by Olesya Astakova in Moscow, Ahmad Ghaddar and Shadia Nasralla in London and Florence Tan in Singapore; Marianna Parraga in Mexico City, Jeff Mason and John Whitesides in Washington; Writing by Dmitry Zhdannikov; Editing by Edmund Blair)