The FTSE 100 and the FTSE 250 were both up 0.5 percent by 0900 GMT, in line with European stocks. The blue chips were up for a fourth straight session and on track for their best week since February 2018.

Markets got a boost when US President Donald Trump said he would meet Chinese President Xi Jinping soon to try to seal a comprehensive trade deal and the top US negotiator reported "substantial progress" in two days of high-level talks.

Banks and mining shares were the top boosts to the FTSE 100 as signs of an impending deal helped the sectors most sensitive to the global economy.

But data showing China's factory activity shrank by the most in almost three years in January kept gains muted.

Weak earnings updates also weighed.

TalkTalk shares sank 7.8 percent to a more than 7-month low after the broadband firm said full-year earnings would fall short of expectations due to higher costs from attracting more customers and changing its accounting standard.

On the FTSE 100, signs of a trade deal nearing boosted luxury goods maker Burberry, among the most exposed to the world's second largest economy, rose 1.6 percent.

Glencore fell 0.6 percent, among a handful of blue-chip losers, after Katanga Mining said the Democratic Republic of Congo asked it to suspend a project. Glencore owns a majority stake in Katanga.