The FTSE 250 midcap index jumped 1.1% to just short of a one-year high, with gains across all but two sectors.
The more internationally focused FTSE 100, meanwhile, rose 0.1% to a one-month high.
A sell-off in utilities and pharma stocks, which are generally considered safer bets at times of uncertainty, weighed on the FTSE 100 as investors turned to riskier assets.
While two Bank of England (BoE) policymakers voted to lower interest rates to ward off an economic slowdown, others including Governor Mark Carney said they would consider a cut if global and Brexit headwinds do not ease.
That helped the FTSE 250 to its best one-day performance in nearly a month.
Global markets welcomed news that Washington and Beijing had agreed to cancel tariffs imposed during their months-long trade war in different phases.
London-listed miners <.FTNMX1770> and Asia-focused banks rose as a result.
Insurer Hiscox, however, slid 10% on its worst day in 17 years and was the biggest faller on the main bourse after at least four brokerages slashed their price targets on the stock by as much as 460 pence.
"We were left with the distinct impression that Hiscox is preparing for a casualty catastrophe, the likes of which haven't been seen since the turn of the century," Jefferies said following analyst meetings with the company.
RSA Insurance, on the other hand, climbed 4% after posting strong profits.
Midcaps benefitted from a flurry of upbeat results, led by a 9% surge in Bank of Georgia following a third-quarter update.
Other results-driven moves saw engineering firms IMI and Wood Group jump 7%, while insurer Lancashire and sweeteners firm Tate & Lyle advanced roughly 5%.
Sub-prime lender Provident added 3% after saying it expected to add more customers at its home credit business, which it has vowed to return to profitability after rejecting a hostile takeover offer from smaller rival Non-Standard Finance in June.
On the downside, engineering firm Senior dropped 8% after warning of a bigger hit to from its aerospace unit from the grounding of Boeing 737 MAX jets.
Among smaller stocks, fashion group Superdry climbed 9.1% after a half-year update and mall operator Intu Properties, which sank 17% in the previous session on the prospects of a cash call, rose 5%.
By Shashwat Awasthi and Muvija M