The FTSE 100 and Europe’s other largest markets dived into the red as the UK’s decision to remove France from its travel corridor hit sentiment.
Travel firms slid in value after the restrictions were announced, as it also raised broader concerns over the impact of the virus.
British Airways owner IAG was the heaviest faller of the day as British holidaymakers cancelled plans to head across the Channel.
London’s top flight closed 95.58 points lower at 6,090.04 at the end of trading on Friday.
Connor Campbell, financial analyst at Spreadex, said: “There were numerous reasons why investors were feeling a bit angsty this Friday.
“Covid-19 has lurched back into the spotlight, sparking a wave of worry about the cost of the crisis.
“Though markets shook off the week’s – admittedly long-teased – second-quarter GDP contraction in the UK, a worse-than-forecast Chinese retail sales reading seemed to pose more of a problem for traders.”
The French markets were also particularly impacted by the quarantine announcement, while global markets were kept low by concerning economic figures from China.
The German Dax decreased by 0.71%, while the French Cac moved 1.58% lower.
Across the Atlantic, the Dow Jones opened lower after a mixed set of US retail figures, but crept higher later in the session as tech stocks made improvements.
Meanwhile, sterling finished the week on an upbeat note, lifting higher while the euro slipped back after employment data for the second quarter showed the eurozone had lost half of the jobs it had created since the financial crisis.
The pound rose 0.26% versus the US dollar at 1.310 and was up 0.1% against the euro at 1.107.
Oil firms and engineering firms also drifted lower as they were weighed down by concerns over the continued impact of the virus on global travel.
In company news, Ten Entertainment and Hollywood Bowl both jumped in value after bowling alley operators were given the green light to reopen after months of lockdown.
The news sent Hollywood Bowl shares up by 22.5p to 162.5p as investors took heart from the long-delayed reopening, while Ten Entertainment rose by 2.5p to 127p.
Elsewhere, shares in troubled fashion retailer Quiz jumped after it secured an increase and extension to its existing loan facilities from lender HSBC.
It closed 1.04p higher at 7.25p after the company, which has been hammered by the lockdown, doubled its banking facilities to £3.5 million.
EasyJet fell in value after it sold 23 planes to a subsidiary of China’s fifth largest bank, netting around £608 million in proceeds as a result.
It closed 40p lower at 570.8p as it was also impacted by wider concerns affecting the travel sector.
The price of oil slipped lower as news of new travel quarantines added to concerns over weak demand in the energy market.
The price of a barrel of Brent crude oil decreased by 0.86% to 45.76 US dollars.
The biggest risers on the FTSE 100 were Barclays, up 1.12p at 109.2p, Smurfit Kappa, up 24p at 2,725p, Natwest, up 1p at 115.75p, and Next, up 48p at 5,950p.
The biggest fallers of the day were IAG, down 9.85p at 194.55p, Aveva, down 191p at 4,364p, Rolls-Royce, down 10.6p at 257.1p, and GVC, down 30.2p at 769.8p.