A British-born jihadi who claims to be fighting in Syria has branded his former country “pure evil” and said he will only return to the UK when the “black flag of Islam” is hanging outside Buckingham Palace.

According to the Daily Mail, the man, who referred to himself as Abu Osama, told a British radio show that he was in Syria taking part military training with the rebel Al Nusra front, which is linked to Al Qaeda. He claimed to be fighting for the establishment of an Islamic caliphate across the Muslim world, and said he had no intention of coming home.

Speaking to BBC Radio 5 Live’s Nicky Campbell, he said: “There is nothing in Britain – it is just pure evil.

“If and when I come back to Britain it will be when this Khilafah – this Islamic state – comes to conquer Britain and I come to raise the black flag of Islam over Downing Street, over Buckingham Palace, over Tower Bridge and over Big Ben.”

He added, however: “I have no intention of coming back to Britain, because I have come to revive the Islamic Khilafah. I don’t want to come back to what I have left behind.”

Speaking of how his family reacted to his decision to go to Syria, he said that they were sceptical at first but now fully support him.

“At first it was hard for them to accept, because no mother wants to lose her son.

“But I send them photos and I speak to them about the situation, and now they can understand that this is a good cause I am in.

“They are a bit scared but I tell them we will meet in the afterlife. This is just a temporary separation.

“They said, ‘We understand now what you are doing’, and my mother said, ‘I have sold you to Allah. I don’t want to see you again in this world’.”

The comments were broadcast as more young British-born Muslims head to Syria to fight for rebel Jihadists there. Earlier this week, Nasser Muthana, a former student in Cardiff posted an image on Twitter of homemade bombs he had purportedly made. He accompanied this with a message saying that Britain “fears” his return.

Muthana had previously appeared in a propaganda video for ISIS, the jihadist group who have declared a caliphate in Iraq and Syria.

ISIS and the Al Nusra front are rival jihadist groups in Syria who have been fighting each other as well as the forces of Syrian president Bashar al Assad. Last week Breitbart London reported how ISIS had crucified several Al Nusra fighters for being “too moderate”.