An expert has revealed the "only two scenarios" that could lead to a Russia-NATO conflict as Vladimir Putin continues his campaign against the alliance.
Vuk Vuksanovic, a political scientist and associate at the London School of Economics IDEAS, warned that either option would come with "the risk of the use of nuclear weapons".
As Russian troops gear up for a summer offensive, which could begin imminently, experts have warned that other members of the alliance could be at risk if Ukraine is not able to thwart it.
Vuksanovic explained two possible scenarios that could lead to a Russia-NATO conflict: a NATO interention in Ukraine or an outright invasion of a member state.
He told Daily Express US: "There are only two scenarios for the NATO-Russia conflict. Either the scenario where NATO intervenes on behalf of Ukraine or the one where Russia invades a NATO member state."
READ MORE: Vladimir Putin dealt major blow as key weapon proving to be 'major flop'
However, Vuksanovic stressed that "both options are unlikely".
This comes as Joe Biden warned of a Russian "direct attack" on NATO should they defeat Ukraine. He said: "If Putin triumphs in Ukraine - the next move for Russian forces could very well be a direct attack on a NATO ally.
"You all know full well that invoking Article 5 … Declared an attack on one is an attack on all. If Putin attacks a NATO ally like he’s attacking Ukraine today, we’d have no choice but to come to their aid."
He made the shocking declaration after signing into law the new $61 billion (£48 billion) aid bill for Ukraine, the first shipment of which is due to arrive imminently, according to US officials.
It is expected to include air defence capabilities, artillery rounds, armoured vehicles and other weapons to shore up Ukrainian forces who have seen morale sink as Putin has racked up win after win.
Russian officials reacted furiously to news of the Ukraine aid bill, warning that it will only increase the Ukrainian death toll.
According to reports in Russian state news agencies, Kremlin spokesperson Dmitry Peskov blamed "the Kyiv regime" for exacerbating the war and causing more deaths.
He said: "The decision will make the United States of America richer, further ruin Ukraine and result in the deaths of even more Ukrainians, the fault of the Kyiv regime."
Related articles
- Moment Russian troops break through Ukraine frontline using 'poison' weapons
- Russia imploding as Vladimir Putin arrests his own top general for 'corruption'
- Warning Ukraine has only six months left as Russia has 'sheer determination'
- Ukraine soldiers make huge rotation error allowing Russians to advance
- NATO-Russia war fears soar as Joe Biden warns of 'direct attack'