Gains in financial stocks and oil majors drove London's main index higher in early trade on Friday, while small-cap Thomas Cook tanked after a proposed 750 million-pound bailout.
The FTSE 100 edged 0.2% higher amid increasing bets that the U.S. central bank will cut interest rates later this month. The mid-cap FTSE 250 added 0.1% by 0710 GMT.
An index of financials companies rose after two sessions of losses, while Shell and BP were also among the biggest boosts to the index in early dealings.
Thomas Cook, hit recently by fading demand for packaged holidays and high debt, slumped more than 30% on a proposed bailout which would hand control of its packaged-tour business to largest shareholder Fosun Tourism.
Small-cap Lookers, whose shares have almost halved in value this year as the car dealership chain battles weaker car demand in Britain, sank 26% after it warned on annual profit.