Investors were (once again) hopeful the US and China may be able to resolve their trade war as President Donald Trump suggested he could extend a deadline beyond 1 March to avoid further tariffs.
According to reports, any possible extension depends on progress in talks.
The FTSE 100 was the biggest riser among European and US stocks, rising 0.8% to 7,190, nearly a new high for 2019.
On Wall Street, the S&P 500 led the charge, gaining 0.3% to 2,753 at around 4:45pm UK time.
Brent crude oil jumped 1.8% to $63.58 per barrel.
LARGE AND MID CAP RISERS AND FALLERS
Packaging group Smurfit Kappa firmed 7% to £24.24, despite the company swinging to an annual loss after it discontinued its operations in strife-torn Venezuela. Underlying earnings rose as management improved margins by successfully passing higher input costs onto customers.
Shares in rival DS Smith rose 4.3% to 350.5p on Smurfit Kappa's results.
Shares in Whitbread were up 2.9% at £49.01 as it set out its plans for long-term value creation in the UK and internationally at its Capital Markets Day.
Mining house BHP gained 2.4% after it approved almost $1bn of spending on new oil prospects in Mexico and the US Gulf of Mexico.
Jet engine maker Rolls Royce rose 3% to 941.6p on reports that Airbus may end production of its A380 super jumbo jet in favour of smaller models.
Hochschild Mining ticked up 0.8% to 192p on news that it would suspend operations at its Arcata precious metal mine in Peru, amid continuing low silver prices and adverse geological conditions.
Also in the resources space, Tullow Oil rose 3.9% to 219.2p after it swung to an annual profit and reinstated its dividend, as revenue rose and it recorded less write-downs.
Elsewhere, Intercontinental Hotels moved to expand its luxury offering by acquiring Six Senses Hotels from Pegasus Capital Advisors for $300m. Its shares added 2.2% to £45.55.
Homewares retailer Dunelm climbed 3.5% to 742.4p on the back of a rise in first-half profit supported by higher same-store sales.
Housebuilder Galliford Try gained 6% to 763.5p, despite booking a fall in first-half profit, as it guided for an annual result at the upper end of market expectations.
SMALL CAP RISERS AND FALLERS
Estate agency Countrywide revealed a 7% decline in annual sales and a 50% fall in earnings as 'challenging' markets took its toll. Its shares were up 10.5% at 10.8p with expectations already set very low.
Immunodiagnostics system supplier Oncimmune shed 5.7% as its annual losses deepened on increased R&D and administrative spending.