The FTSE 100 fluctuated as oil prices returned to $90 a barrel, reigniting concerns over persistent inflation pressures in the UK economy. Energy giants BP and Shell led gains, offsetting losses in rate-sensitive sectors.

Brent crude's climb above $90 came amid supply constraints and geopolitical tensions, complicating the Bank of England's policy outlook. Traders pared back bets on early rate cuts, with money markets pricing in a higher-for-longer stance.

The blue-chip index hovered near 7,600, supported by a weaker pound that boosts overseas earners. However, miners and banks slipped as investors weighed the impact of costlier energy on consumer spending and corporate margins.

Analysts warned that sustained oil strength could delay disinflation, keeping the FTSE 100 volatile ahead of key CPI data. "Energy costs remain a wildcard for the inflation trajectory," said a strategist at a London brokerage.