The FTSE 100 touched a new all-time high shortly after the open on Monday, supported by a jump in defence and defence-related stocks after the Ukraine summit hosted by Prime Minister Kier Starmer over the weekend.
Shortly after the open, the blue-chip index was up 32 points or 0.4% at 8,841.6.
BAE Systems PLC led the way, jumping 15%, while Rolls-Royce Holdings PLC gained 5%, continuing its results momentum from last week, and Melrose Industries PLC rose over 1%.
On the FTSE 250, defence technology group QinetiQ Group PLC jumped 9.5%, Babcock International PLC 7.6% and Chemring Group 6%.
Small-cap defence stocks are also being lifted after the European defence summit and the prospect of higher spending.
Helmet and gas mask maker Avon Technologies PLC leapt 6.5%, which has been topped by sonar, torpedo and communications specialist Cohort PLC shooting 11.5% higher.