On the first trading day after Britain's exit from the European Union, the FTSE 100 and the FTSE 250 added 0.2pc each.
The blue-chip FTSE 100 was partly supported by exporter stocks such as Diageo Plc as the pound weakened, though gains were countered by a drop in oil major Shell as crude prices slid.
Stock markets in Britain were in stark contrast to those in China, where shares plunged in the first trading session following an extended Lunar New Year break, as the death toll from the virus outbreak rose to 361 in the Asian country.
"As yet the spread of the virus has not reached epidemic levels in Europe or the U.S., but we are entering a key period now and a sharp escalation in cases closer to home would spook the markets," Markets.com analyst Neil Wilson said.
"I would consider the script is likely to be the same as last week with dips drawing in buyers, but for these rallies to lack any conviction."
Though a sharp drop in stock valuations due to the epidemic has made for a more attractive entry point for some dealers, the broader impact has been firmly negative.
Both British benchmark indexes shed more than 3pc last month as the outbreak sapped risk appetite, while global stocks also tumbled.
London-listed shares of Ryanair Holdings Plc jumped 4.2pc on Monday after the Irish carrier raised its annual profit forecast, citing a better-than-expected performance over Christmas and New Year.
Shares of peer easyJet Plc advanced 1.5pc on the main bourse.
An index of housebuilders rose 0.5pc after Credit Suisse began coverage of the sector with a "positive stance".
Among midcaps, Future Plc gained 6.4pc after the publisher forecast its full-year results to be materially ahead of market expectations. Small-cap peer Reach Plc also rose more than 6pc.
A notable loser was payments firm Finablr Plc, which gave up almost 4pc. Its unit, Travelex, said on Friday it had partially restored its UK website, more than a month after a crippling ransomware attack.
Brokerage EFG Hermes also downgraded Finablr's stock, which has lost more than half its value since the attack late last year.