The main index gave up 0.4pc to levels last seen in mid-December, as the Bank of England's decision to keep interest rates unchanged supported sterling and hit firms that earn largely in U.S. dollars.
HSBC, Diageo and AstraZeneca were among the biggest drags on the index.
The FTSE 250 recorded a 0.3pc gain, with Aston Martin surging 25pc after Canadian billionaire Lawrence Stroll said he would take a stake in the company.
The luxury carmaker's shares were on track for their best day ever.
The blue-chips lagged the broader European benchmark , which gained despite the World Health Organization (WHO) declaring a global emergency over the China-linked virus, which has killed more than 200 people.
"The WHO's assessment of China's response to the coronavirus outbreak and advice to governments not to 'unnecessarily' block travel and trade seems to have soothed markets a little," Markets.com analyst Neil Wilson said.
"Whilst it declared a global emergency, the message seems to be not to panic."
Still, both British benchmark indexes look set to shed nearly 2.5pc this month, as the outbreak has driven dealers away from risky assets such as stocks.
Smaller stocks saw some sharp declines.
French Connection, the owner of Great Plains and YMC brands, tanked 35pc and was on course for its worst day ever after it dropped plans to sell itself and said it would instead focus on a turnaround.
M&C Saatchi slid 8.5pc as Britain's financial watchdog began a probe after the advertising agency revealed an accounting scandal last year, while fashion retailer Laura Ashley slumped 10pc after its top boss stepped down.
AIM-listed Staffline shed 9pc after the recruiter issued yet another profit warning.
"Given the lack of asset backing in the business, we expect that the banks will seek (Staffline) management to realise cash through disposals or find other sources of finance," Liberum analysts said.