A former British Army sniper heading into the thick of battle in Ukraine believes it is his duty to fight against "modern day Hitler" Vladimir Putin.
Retired soldier Shane Matthews, carrying 60kg of medical supplies which have already been donated to him, said he will hit the frontline to treat wounded Ukrainians and provide training for civilians rising up against Putin's forces.
But the veteran, 34, added he is more than ready to bear arms and fight if necessary.
He has bravely answered the call to arms from Ukraine's President Volodymyr Zelenskyy, who made an urgent plea for foreign fighters to help his country over the weekend.
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Matthews, who completed multiple tours of Afghanistan and Iraq, will be flying out to Poland on Monday before crossing the border and meeting a Ukrainian colonel, who has agreed to "arm him" and 21 others.
The experienced sniper, who served as a Lance Corporal with the 2nd Battalion Princess of Wales' Royal Regiment for six years until 2009, then aims to travel to Kyiv, where Russian rockets have reportedly been causing widespread devastation.
He said he took the decision to mobilise after foreign secretary Liz Truss said she would "absolutely" support Brits volunteering to fight in defence of Ukraine, saying the battle was crucial to protecting "freedom and democracy" in Europe.
Mr Matthews, from Chichester, West Sussex, said: " Russia is trampling on the democratic rights of an entire nation illegally and nobody is trying to stop it.
"What Russia has done is disgusting. It is beyond reprehensible. Russian people don't want to be involved. The Russian military doesn't know why they're there.
"As far as I'm concerned, if you can fight it's your duty to fight. You're looking at modern day Hitler steam-rolling across Ukraine."
Mr Matthews is believed to be among the first Brits to join Ukraine's newly-formed "International Brigade" which President Zelenskyy announced on Sunday.
He will be flying out alongside two Ukrainians living in the UK and meeting several friends from his regiment who have also joined the war effort.
Mr Matthews added: "My friends were not surprised I wanted to do it, they expected it. My family were not too happy.
"I have several others from my regiment who I'm meeting out there. There's six of us who all did the same tours in Afghanistan. It's going to make the fighting side a lot easier because we all know how each other operates."
His mission has been backed by the veteran community across West Sussex and Hampshire, who have come to his aid in providing military kit and medical supplies.
Defence secretary Ben Wallace said he didn't "want to see British people killed any more than I want to see Ukrainians" and asked people who were not properly trained or an "experienced member of an armed forces" not to join the war in Ukraine.
