The commodity-heavy FTSE 100 rose 0.3%, with shares in oil majors BP and Royal Dutch Shell jumping more than 2% as an ongoing global energy crunch drove U.S. crude futures to $80 a barrel for the first time since 2014. [O/R]
The domestically focused mid-cap index, however, eased 0.1%, with UK-listed shares of travel company Tui slumping 15.5% as a rights issue got underway.
Czech company Eurowag -- which initially planned to float on Thursday -- dropped some 10% to 135 pence, falling below its offer price of 150 pence per share.
"There is usually a significant amount of volatility immediately after trading begins with IPOs. So, volatility in itself is not unusual and (Eurowag) shares have fallen, given that the offer price came in below the initial range indicating that demand was rather subdued," said Susannah Streeter, an analyst at Hargreaves Lansdown.
Europe's initial public offering market had its strongest third quarter in a decade, though inflation fears and concerns over a property crisis in China have soured investors' appetite for new stock listings.
While concerns about soaring gas prices and labour shortages have sent the midcap index on its worst weekly run since 2018, banks and oil stocks have driven weekly gains for the FTSE 100.
Shares in British Airways-owner IAG and Ryanair edged up as Britain was set to scrap tough COVID-19 quarantine requirements for 47 destinations.
Weir Group fell 2.5% after saying it was the target of an attempted ransomware attack in the second half of September, which impacted its third-quarter profit.
Graphic: UK midcaps set for worst weekly losing streak since Dec 2018 
(Additional reporting by Sruthi Shankar; editing by Uttaresh.V, Kirsten Donovan)
By Shashank Nayar and Bansari Mayur Kamdar
