A man accused of terrorist-related offences laughed at claims he used a ball of socks found with traces of explosives on it to clean mortar bombs.
Mr Rowe said explosive traces on his socks related to work in Bosnia
Andrew Rowe, 34, of west London, told the Old Bailey he used the sock ball as a martial arts training aid.
Mr Rowe said explosives traces may have been present because he had used them as gloves to unload ammunition during volunteer work in Bosnia in 1995.
He denies terror charges including one of having items for use in terrorism.
Mr Rowe, from Maida Vale, told the court he converted to Islam at the age of 19 in a bid to alter his lifestyle after taking and selling drugs.
He was arrested in the Channel Tunnel in October 2003 as he travelled to the UK after a trip to Germany.
The ball of socks in his luggage was found to bear traces of three explosives used in Russian 82mm mortars.
The prosecution has said the socks, which had been rolled into a ball and attached to a pyjama cord, could have been used to clean a mortar launcher barrel, or used as a mortar bung.
But Mr Rowe laughed out loud at the claims, but then apologised for his outburst.
He went on to deny the allegation, saying he had volunteered to go to Bosnia as a driver but was put to work unloading boxes of ammunition.
It was then that he used the socks as makeshift gloves to prevent splinters in his hands, he said.
Mr Rowe said: "The boxes were breaking. I did not want to get splinters.
"I tried to buy some gloves but I could not find any, so I used my socks over my hands."
The explosive traces remained because he had not washed the socks, he said.
He had since attached the cord to the sock ball so he could hang it up and kick it when practising martial arts, he added.
The suspect also said a notebook found in his former flat with 20 pages of notes on how to use a mortar were related to his time in Bosnia.
Mr Rowe said he had been shown a book about mortars when he had said he wanted to do more than unload boxes.
He told the Old Bailey he transferred the notes he had made in Bosnia, into the notebook upon returning to the UK "to be a bit of a lad".
"When I spoke to people, I could look as if I had authority," he said.
Mr Rowe is also accused of having a code to communicate in secret with others and a notebook with details on how to use mortars at addresses in London and Birmingham.
He said had been to Germany earlier that year to meet a man to find out about helping with humanitarian aid to Chechnya.
Here was given a code to copy to allow for instructions to be sent in secret in which "targets" referred to bordering countries where aid would be taken, he told the court
He also said he was told acetone and H2O2 were explosives but they would not be used for terrorist purposes.
He said: "I had that surety from working with that man before that it would not be of a terrorist nature.
"They were going to help the Chechens defend themselves in Chechnya."
The trial continues.