China will cut additional tariffs levied against 1,717 US goods last year, after a Phase 1 trade deal was signed last month, and as fears persist over the coronavirus outbreak, which has killed more than 550 people.
The FTSE 100 rose 0.3pc. The FTSE 250 added 0.4pc, as insurer Beazley gained 6pc after its 2019 profit surged.
Royal Mail sank 8pc after the letter carrier warned outlook for the 2020-21 fiscal year was "challenging" and said the threat of a labour strike in late 2019, hurt parcel revenue growth during the Christmas period.
The company's strained relationship with the CWU union, which has called for a strike ballot, "bodes ill for both business as usual productivity improvements and reaping the benefits of the medium-term strategy," Liberum analyst Gerald Khoo wrote.
Global markets have been attempting a recovery after sharp losses last week, and were given a shot in the arm on Wednesday by media reports that scientists had developed a drug against the China-linked virus.
Though the World Health Organisation played down the reports, hopes that the outbreak would soon be contained as well as upbeat economic data from the United States helped boost stock bourses.
"The momentum is clearly with the bulls at the moment, and we see no reason to stand against that tide," OANDA analyst Jeffrey Halley said.
"The potential for an aggressive and rapid correction lower still lurks though, if negative Wuhan virus headlines emerge," he warned, adding that economic data for January was yet to show any severe spillover in growth from the virus.
GlaxoSmithKline slipped 3.6pc, following a more than 4pc drop in the previous session when its fourth-quarter earnings missed analysts' estimates.
NMC Health, whose shares have been battered after criticism from short-seller Muddy Waters late last year, was up 3pc after soaring as much as 13pc in early deals.