The stock was also the single biggest boost to the FTSE 100, which rose 0.2% but was still held back by a mixed batch of quarterly earnings reports and a slide in shares of BP Plc and Royal Dutch Shell Plc.
The domestically focussed FTSE 250 climbed 0.3% on a 4.9% jump in Direct Line Insurance Group Plc after the company reported a 70% drop in motor insurance claims for April with fewer people driving due to lockdown measures.
The blue-chip FTSE 100 kicked off May on a dour note last week following a strong rebound in April as investors feared the halt in business activity due to sweeping lockdown measures had pushed the global economy into deep recession.
Although several hard-hit countries have now started easing restrictions, analysts have warned that economic data would get worse before showing improvements.
In company news, online supermarket Ocado jumped 2.7% after saying retail revenue had soared 40.4% year-on-year so far in the current quarter on higher demand for home deliveries.
Transport firm National Express Group added 4.6% as it said it planned to raise equity to shore up its balance sheet and that it had secured debt waivers through 2020 to ride out an economic slump.