Bingle was appearing before the Commons public administration select committee last week as part of its ongoing lobbying inquiry.
It has been reported that Bell Pottinger has represented Iraq, Syria and Afghanistan, but Bingle insisted that this work was not undertaken by the company's public affairs arm.
Bingle also revealed that Bell Pottinger Public Affairs had declined to work for Zimbabwe. However, he said the agency was happy to represent most legitimate causes.
'If there is an ethical case to be made, which is also a legal case that has a right to be heard, then Bell Pottinger would probably be prepared to make that case,' Bingle told the MPs.
Later in the session, he claimed: 'We disclose 99 per cent of our clients. On our website today, most of our clients are there. Occasionally clients will ask us to sign a non-disclosure agreement - if there is a potential bid where it would be unwise.
'But even if we are working for a client whose name is not public, when my staff deal with government ... they will say on whose behalf they are calling.'
Bingle also insisted: 'The public have no right to know who our clients are.'
The Bell Pottinger lobbyist defended his agency's decision not to join the Association of Professional Political Consultants (APPC).
He said: 'We agree with everything in the various codes apart from one thing - we are not prepared to join the APPC and then break the rules by saying we will declare our clients when we cannot.' He added that his staff were members of the CIPR and therefore adhered to the 'very, very stringent, quite draconian' CIPR code of conduct.
Appearing alongside Bingle was Luther Pendragon partner Mike Granatt, who took a similar line to Bingle over his agency's refusal to join the APPC. Granatt said: 'Our only problem ... is this business about client confidentially - that is the only issue.'
DLA Piper lobbyist Eben Black was also questioned by the MPs in a subsequent session.
BINGLE GRILLED ON FOREIGN CLIENTS: EXTRACTS FROM THE HEARING
Peter Bingle: We will turn down clients. We had a call from Zimbabwe asking to advise them, we said thank you very much but no. It would have been a fairly malign campaign.
Gordon Prentice MP: Was Zimbabwe a one-off? Would you take commission from the North Korea government, for example?
PB: I would have thought not. What we do often, if we get a call from an overseas client, we would talk to the foreign office, take a view, look at whether we would want to work for that type of country or company.
Ian Liddell-Grainger MP: There was a furore when Chile's former dictator General Pinochet came over and was arrested. Were you looking after him at that time?
PB: No. Bell Pottinger Public Affairs deals with things such as financial services and UK public policy. We are part of a wider group. That wider group does advise presidents and countries.
ILG: Do you do anything for the Pinochet family at all?
PB: At Bell Pottinger Public Affairs, no.
ILG: What about Mark Thatcher? Are you still looking after him?
PB: We don't tend to deal with individuals. We tend to deal with PLCs, we don't really tend to deal with personalities.
ILG: I think you work for Syria or Saudi Arabia, are you working for them?
PB: At the moment Bell Pottinger Public Affairs is working for neither Syria or Saudi Arabia.
ILG: What other countries are you working for at the moment?
PB: We have a small piece of work for Japan's embassy in London, and one of my colleagues is currently in Abu Dhabi. That's it.