Islamic State: Ex-UK soldier wants to train Kurdish forces
A former British soldier has told the BBC he plans to go to Syria and fight Islamic State (IS) militants to help make it a "better place" to live.
The unnamed man, who wants to train Kurdish fighters, said the "vile" extremists were "terrorising" people.
The BBC understands about 100 people from the West - including some Britons - are helping Kurdish militia.
The foreign secretary warned that UK citizens who travel abroad to fight IS could face prosecution if they return.
Philip Hammond said: "Anyone conducting irregular fighting activity overseas is subject to British legislative sanction.
"That is unlawful activity and can be dealt with on their return to the UK."
Speaking to the BBC, the Welsh former soldier said if governments were not helping the people of Syria, "then why can't ex-service personnel?".
"I am not happy in this country. I do have two children but there is nothing in this country that I can honestly be proud of," he said.
"The only thing I can be proud of was being part of the British forces - the best forces in the world - and why not continue that knowledge and show that knowledge to other people?
"If I want to be happy and do something I know I am good at, why not?
"I want to help these people and nothing is going to stop me. I am going."
More than 500 Britons are believed to have travelled to join IS.
The UK government says taking part in a conflict overseas, no matter what side the person is on, could be an offence under both criminal and terror laws.
David Anderson QC, the government's independent reviewer of terrorism legislation, told BBC Radio 4's Today programme that unlike some countries, the UK does not have an explicit law against going to fight abroad.
"That's not to say that what you are going to do there is necessarily lawful," he said.
Someone could be prosecuted if they committed war crimes or fought for a terrorist organisation, he added.
"The definition of terrorism is both broad and complicated," said Mr Anderson. "It doesn't just catch people fighting for terrorist organisations.
"It could also catch people who are fighting against terrorist organisations.
"It depends on whose side you are on and motives. If he was doing it for the money, then he wouldn't be a terrorist - mercenaries cannot be terrorists. You need to be doing it for a political or ideological or religious or racial reasons."
It might not always be in the public interest to pursue a prosecution, he added, as prosecutors would be aware of how a jury could view someone who said they hated terrorism and had been fighting for humanitarian reasons.
"The law is ambiguous," he added. "You could take the view that if you really wanted to stop people fighting abroad for whatever reasons, you ought to have a law.
"As soon as you start trying to make people into terrorists, even on the face of it when they don't really look very like terrorists, then you get into difficulties."
Earlier this month, former British soldier Konstandinos Erik Scurfield was killed in Syria while fighting alongside the 30,000-strong Kurdish forces.
On Monday, German woman Ivana Hoffmann was reported to have been killed in Syria while fighting alongside Kurdish militia.