British stocks broke a three-day losing streak on Monday as strong economic data from the United States and China boosted investor confidence, while travel companies benefited from rising demand for holidays beyond the European Union.
The FTSE inched up by 0.2 percent and midcaps were up 0.3 percent.
Travel groups supported the main index as British holidaymakers drove demand for destinations further afield given the contortions over Brexit.
London-listed shares of German tour operator TUI advanced nearly 3 percent to their highest since mid-February, while British Airways owner IAG and EasyJet added 2 percent and 1 percent, respectively.
The world's oldest travel group, Thomas Cook, jumped 4.1 percent on the small-cap index.
"US GDP has bolstered risk appetite, and the banking numbers out of the UK have been solid thus far, on hopes that growth is looking better around the globe," IG Markets analyst Chris Beauchamp said.
Gains on the FTSE 100 were spread across financials, industrials and healthcare stocks.
Asia-focused HSBC gave the index its biggest boost following upbeat quarterly results from Industrial and Commercial Bank of China,, the world's largest commercial lender by assets.
"Any good news from the Chinese banking sector would potentially be a signal of some decent results for HSBC on Friday," Spreadex Analyst Connor Campbell said.
Barclays also added 2.3 percent, gaining some ground lost last week following a slump in profits.
Online supermarket Ocado's shares ended 0.6 percent lower, after falling as much as 5.4 percent, as it said an electrical fault caused a blaze at a major distribution centre earlier this year.
Oil majors Shell and BP weighed on the index as crude prices weakened after US President Donald Trump demanded that producer club OPEC raise output to soften the impact of US sanctions against Iran.
On the midcap index, Ferrexpo rose 5.7 percent with a trader saying that markets had focused on positive comments on the miner's performance over the ongoing scrutiny of use of funds at a charity partner.
Banks were the second biggest risers on the FTSE 250.
"Broadly the UK banking stocks didn't have a great time last week... It could be just a case of on a quiet day, people fishing about thinking that perhaps the banks are being oversold," Campbell said.