The blue-chip index rose 0.5%, boosted by a 4% jump in Unilever Plc and Reckit Benckiser, and a 2% rise in AstraZeneca.
However, Royal Dutch Shell and BP fell 2% and 0.4%, respectively, as the U.S. crude futures contract plunged more than 50% on worries about lack of storage and a weakening global economy.
The FTSE 250 midcap index, guided more by the outlook for the domestic economy, slipped 0.2% as UK officials said it was too soon to talk about easing the lockdown imposed to control the spread of the coronavirus.
After a late rally last week on signs of gradual restarting of economies, stock markets globally pulled back on Monday as investors braced for dismal earnings reports and economic data.
"Now we've got people asking companies questions that have never been asked - how many weeks or months of liquidity do you have looking at your current cash flow and revenue if the lockdown lasted longer," said Benji Dawes, who co-manages the UK Growth Fund at Premier Miton.
"That's why we're starting to see companies raising equity. It is a function of these companies trying to make sure there is as much liquidity as possible in case of a longer lockdown."
Sofa retailer DFS Furniture surged 11% after revealing plans to issue equity of up to 19.9% of its existing share capital and negotiate an additional debt facility to get it through the crisis.
Mr Kipling cakes maker Premier Foods soared 29% after it forecast annual trading profit to be at the top end of market expectations as Britons stocked up on food at the start of the lockdown.
Investors are expecting the health crisis to erode first-quarter profit for companies listed on the pan-European STOXX 600 index by 22%, according to Refinitiv data.
Analysts at J.P.Morgan Cazenove said in a client note that hopes that markets will focus on better earnings in 2021, rather than weak numbers this year, might be dented.
"Equities are much less forward-looking than commonly assumed, their prices tended to be almost coincident with activity and earnings movement," they said.
Despite recovering from mid-March lows due to massive stimulus measures by major central banks and governments, the FTSE 100 remains down more than 24% from its January peak.
Property website Rightmove said it was unable to provide meaningful house price data due to a collapse in the number of new homes being listed for sale in Britain.
Shares in housebuilders Barratt Development, Taylor Wimpey and Persimmon were down 2% to 5%.
Pub operator Marston's fell 3.8% as it secured a waiver from its banking backers for potential breaches of its debt commitments, highlighting the extent of damage wrought on UK pubs and restaurants.
By Devik Jain and Sruthi Shankar