Defence and aerospace companies powered the gains in London on Thursday, with BAE Systems PLC (LSE:BA.) rising 6.3% at the top of the FTSE 100 leaderboard.
Defence contractor Babcock International PLC (LSE:BAB) was up 2.7% and Rolls-Royce Holdings PLC (LSE:RR.) 2.2% higher.
This comes after Poland said that Russian drone incursions last night "did not veer off course" but were deliberately targeting Poland.
Polish prime minister Donald Tusk said today that calls with European leaders led to "not only expressions of solidarity with Poland, but above all, proposals for concrete support for the air defence of our country".
Last night, Ukrainian president Volodymyr Zelenskyy said European countries need to work on a joint air defence system.
Zelenskyy said in a social media post that Russia’s deployment of drones was an act of "brazen behavior".
He said: "We need to work on a joint air defense system and create an effective air shield over Europe. Ukraine has long proposed this, and we have concrete solutions.
"We must respond together to all current challenges and be ready for potential threats to all Europeans in the future.
"Likewise, we need to significantly increase joint funding for the production of interceptor drones. They have already proven their effectiveness."
BAE Systems subsidiary Malloy Aeronautics, bought last year, makes 'novel aircraft' and drones, and the group is also developing uncrewed air systems and capabilities such as 'attritable' systems for military customers, such as unmanned aerial vehicles.
Babcock, according to its website, develops uncrewed aerial systems for defence surveillance and reconnaissance as well as with weapons capabilities.
Investment analysts at AJ Bell said: "Ongoing geopolitical tensions have led investors to have confidence in the defence sector, believing earnings prospects are strong given a fragile backdrop."
BAE Systems’ share price has risen by 48% over the past 12 months and more than 250% over the past four years.
Government data today showed the Ministry of Defence expenditure has risen 6% in real terms to £31.7 billion, including a 21% uplift to investment in the weapons and ammunition sector after inflation.
The figures show the highest level of defence investment in UK industry for over a decade.
Defence Secretary John Healey said: "These new figures show how the defence dividend from our record investment is benefitting working people across the UK. It follows the launch of our Defence Industrial Strategy this week, which will provide the resilient industrial base that we need for the future."