A strong showing by the oil majors on the back of soaring crude prices was not enough to drive the FTSE to gains after an afternoon decline left London’s top index marginally lower.
A near-three-year high in the price of crude had lifted BP and Royal Dutch Shell higher and they helped pull the index up from midday after a mixed start.
However, inflation concerns and a rebound in sterling ultimately weighed on London stocks.
London’s top flight closed 15.95 points, or 0.22%, lower at 7,074.06 on Wednesday.
Chris Beauchamp, chief market analyst at IG, said: “The rebound in risk appetite continues to fizzle out, with equity indices mostly unimpressed by the ongoing high PMI readings that signal a continued economic rebound.
“At least oil can still be relied on, as yet another drop in US crude stockpiles pushes Brent and WTI to new multi-year highs.”
Predictions of the demise in oil usage have not materialised and the surge in demand from recovering economies saw it tip over the 75 dollar mark.
Brent crude increased by 1.07% to 75.61 dollars per barrel.
Meanwhile, sterling nudged higher as currency traders were buoyed by the latest flash PMI figures which showed further strong growth in the private sector.
Michael Hewson, at CMC Markets UK, added: “The pound may also be being helped by optimism that the current disagreements over the Northern Ireland protocol will get resolved by way of a more pragmatic approach, between the EU and UK.”
The pound was 0.01% higher versus the US dollar at 1.396 and increased by 0.02% against the euro to 1.170.
Elsewhere in Europe, the other major markets suffered heavier slumps in equity stocks.
The German Dax decreased by 0.93% and the French Cac moved 0.8% lower.
Across the Atlantic, the markets opened higher for the third day in the row as the S&P attempted to join the Nasdaq at another record high.
In company news, pharmaceuticals giant GlaxoSmithKline made gains after its chief executive officer Emma Walmsley promised to grow both sales and profits with a new strategy plan for the business.
She said the business expects sales to grow by around 5% and adjusted operating profit by 10% over the next half-decade but added that it will see a 30% dip in its dividend.
The group saw shares improve by 14.4p to 1,409.2p on Wednesday.
Phoenix Group dipped in value after the insurance firm confirmed to investors that reinsurance specialist Swiss Re had sold its 6.6% stake in the London-listed company.
Shares in Phoenix dropped 17.6p to 676p at the close after Swiss Re said it sold its shares in a £437 million move.
BT Group was one of the FTSE’s main risers after brokers at Barclays said its shares have the potential to rise almost 50% to 300p.
Barclays said increased visibility of returns in Openreach has driven positivity as shares lifted by 2.7p to 205.3p at the close.
The biggest risers on the FTSE 100 were JD Sports, up 16.2p at 903.2p, Royal Dutch Shell B, up 21.6p at 1,421.8p, Royal Dutch Shell A, up 20p at 1,472.6p, and BT Group, up 2.7p at 205.3p.
The biggest fallers on the FTSE 100 were Melrose, down 4.3p at 158.1p, Phoenix, down 17.6p at 676p, Informa, down 13.2p at 515.8p, and Taylor Wimpey, down 3.7p at 160.6p.