The FTSE 100 pushed higher on the back of strong showings by consumer and healthcare firms, including a surge in value by NMC Health.
London’s top flight closed 41.11 points higher at 7,623.59 at the end of trading on Monday.
David Madden, market analyst at CMC Markets UK, said: “The FTSE 100 is enjoying a broad-based rally as consumer, industrial, mining as well as health care stocks are higher this afternoon.
“Market movements are low as some traders are tapering off their activity as Christmas is getting closer.”
The other major European markets were mixed, with minor losses or gains on a day of low volatility, despite news that China will lower tariffs on more than 850 US products.
Mr Madden said it was “almost as if traders are indifferent to the positive US-China news”.
The German Dax decreased by 0.12% while the French Cac moved 0.18% higher.
Across the Atlantic, the Dow Jones lifted higher at the start of trading as sentiment was buoyed by the improving tariff scenario, while traders shrugged off a poor durable goods report.
Meanwhile, sterling slid lower as its post-election slump continued. Fears over a no-deal Brexit have weighed on the currency since Boris Johnson secured a majority, although it remains significantly above its value from just three months ago.
The value of the pound decreased 0.66% versus the US dollar at 1.292 and dipped 0.81% against the euro at 1.165.
In company news, a resurgent NMC Health helped to drive the FTSE 100 higher after the hospital operator announced the launch of an independent review into its accounts.
The UAE-focused firm had seen its share price slump heavily over the past week after US short-seller Muddy Waters publicly criticised its financials.
Investors cheered news of its third party review, sending shares 479p higher to 1,779.5p at the close of play.
Cobham nudged higher after it revealed a series of promises made by its private equity suitor that led to the Government waiving through its £4 billion takeover.
The world-leading expert in air-to-air refuelling, said new US owners Advent International would maintain a UK headquarters, continue funding research and development at its Dorset offices and keep using the Cobham name.
Shares in the business increased by 0.65p to 164.35p on Monday.
Vimto manufacturer Nichols plunged in value after it issued a surprise profit warning, blaming a new tax on soft drinks in Saudi Arabia and the UAE for hitting sales.
The Merseyside-based business, which can trace its roots back to 1908, said the 50% levy could lead to profits “materially below” current expectations next year.
Shares in the business fell by 170p to 1,530p.
The price of oil was subdued, moving marginally higher as the price of crude sat near a three-month peak following positive statements regarding US-China trade relations.
The price of a barrel of Brent crude oil rose by 0.48% to 66.34 US dollars.
The biggest risers on the FTSE 100 were NMC Health, up 479p at 1,779.5p, Pearson, up 30p at 654.2p, Bunzl, up 64p at 2,115p, and Melrose, up 6.6p at 239.2p.
The biggest fallers on the index were BT Group, down 2.2p at 202.05p, Prudential, down 13p at 1,430p, AstraZeneca, down 62p at 7,746p, and 3i, down 8.5p at 1,097.5p.