Part of the SFO’s case is that the advisory agreement, which the defendants claim was a vehicle for Barclays to tap into the Gulf’s oil and gas market, did not provide concrete value for the bank.
Kalaris said: "Even if the ASA were unconnected to the capital raising, it would have been a good idea for the bank to enter into it.
"The first ASA made good business sense to me at the time and it still does now.
"I stressed to Mr Boath that someone might allege that the ASA was not economic," explained the defendant, adding that the agreement had been kept deliberately vague because the Qataris wanted greater flexibility.
"Richard Boath and I were giving sensible consideration to the idea that the ASA was not economic.
"In the end, the decision was taken by senior management and the legal department to disclose the fact of the ASA but not to disclose the amount being paid under the prospectus.
"I had no responsibility for the content of the prospectus. It was not within my remit and was handled by our financial director.
"I only operated within the realms of what the bank was advised was legal and right."
Prosecutors allege that the bankers were motivated by a fear that Barclays would have to be bailed out and that their lucrative salaries would be terminated as a result.
Varley, of Notting Hill, Jenkins, of Malibu, California, Kalaris, of Knightsbridge, and Boath, of Henley-on-Thames, Oxfordshire, deny fraud by false representation, between 1 May 2008 and 31 August 2008.
Varley and Jenkins deny a second like charge of fraud by false representation, between 1 September 2008 and 30 November 2008.
The trial continues.