Britain's armed forces must be prepared to "fight and win" to prevent the spread of war in Europe, the new head of the British Army is warning.
In a speech on Tuesday, Gen Sir Patrick Sanders, the Chief of the General Staff, will say he had never seen such a clear threat to peace and democracy as the "brutal aggression" of Russian President Vladimir Putin.
Gen Sanders will liken the current situation to the run up to the Second World War, saying Britain must be prepared to "act rapidly" to ensure it is not drawn into a full-scale conflict through its failure to contain Russian expansionism.
His latest warning, in an address to a conference organised by the Royal United Services Institute think tank, comes after he wrote to all of the troops under his command, telling them they must prepare "to fight in Europe once again".
Speaking at the same event, UK Defence Secretary Ben Wallace is expected to issue a new call for increased defence spending in the years ahead to counter the growing threat.
UK Prime Minister Boris Johnson is preparing to join other leaders in Madrid for a Nato summit at which they are expected to agree to the biggest overhaul of Nato since the end of the Cold War.
In his first public engagement since taking up his post, Gen Sanders will say his focus is on preventing the spread of war in Europe by having the army "ready to fight and win alongside our Nato allies and partners".
"In all my years in uniform, I haven't known such a clear threat to the principles of sovereignty and democracy, and the freedom to live without fear of violence, as the brutal aggression of President Putin and his expansionist ambitions," he is expected to say.
"This is our 1937 moment. We are not at war, but must act rapidly so that we aren't drawn into one through a failure to contain territorial expansion.
"I will do everything in my power to ensure that the British Army plays its part in averting war."
Traditional warfare not anachronistic
Despite the recent emphasis on new capabilities, such as drones and cyber warfare, he will say that land forces will remain crucial in any conflict.
"You can't cyber your way across a river."
In a reference to the start of the First World War, Gen Sanders will say that "this is not the rush to war at the speed of the railway timetables of 1914".
Instead he will say deterring Russia means "more of the army ready more of the time", from "the general in [Ministry of Defence] main building to the young lance corporal in the barrack room; from the reservist on a weekend exercise to the civil servant in army headquarters".
Mr Wallace will repeat his call for increased investment in defence to meet the changing international environment.
In March, he wrote to UK Chancellor Rishi Sunak before his spring statement, warning UK defence spending was set to drop below the Nato minimum of 2 per cent of GDP by the middle of the decade unless the Treasury committed more resources.
"The defence secretary is expected to emphasise that now that the threat has changed, governments must be prepared to invest to keep us safe," a PA defence source said.
Nato military alliance - in pictures
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A solemn welcoming ceremony of US soldiers at Adazi military base, Latvia, on February 25, 2022. More than 300 soldiers of the 173rd Air Force Brigade arrived to demonstrate the US commitment to defend Nato allies and strengthen Latvia's defence capabilities following Russia's military operation in Ukraine. EPA -
US paratroopers in Ukraine's western Lviv region during a Nato-sponsored training exercise in 2020. AP -
A US military aircraft takes off at the US Air Base Ramstein, in Landstuhl, Germany, on February 25. US President Joe Biden February 24 authorised the deployment of further armed forces to Germany as part of Nato's response to Russia's military aggression on Ukraine. EPA -
Nato Secretary General Jens Stoltenberg at the alliance's headquarters in Brussels, Belgium, on February 25. EPA -
A convoy of British armoured vehicles of the Royal Welsh Battlegroup on the way to Estonia, driving through Liepupe, Latvia, on February 25. British troops and equipment are heading to Estonia as part of the UK's contribution to strengthen Nato's uplift to Eastern Europe. EPA -
Protesters outside a Nato leaders virtual summit in Brussels on February 25. AP -
A US Air Force F-35 Lightning II aircraft assigned to the 34th Fighter Squadron receives fuel from a KC-10 Extender aircraft over Poland on February 24. US Air Force/Reuters -
US military personnel check an Apache attack helicopter AH-64 during a technical stop on the tarmac at Traian Vuia International Airport in Timisoara, Romania, on February 24. EPA -
German soldiers of the Nato enhanced Forward Presence (EFP) Battalion Battle Group in Lithuania attend a ceremony during a visit of German Defence Minister Christine Lambrecht to Rukla Military Base, Lithuania, on February 22. EPA
