I tried both etrade and cmc, which could not help, but as daverobev suggested, I also tried IB. It seems as though it is possible to open an account with them, telling them I want to fund it with GBP. I then transfer money from my existing GBP account to my IB account (GBP > GBP means no currency conversion). I then can trade directly on the UK market, buying with GBP. If I purchase on another market, then my funds would be converted to the applicable currency....which I don't intend doing. If at any stage I want to sell my holdings, once the funds are redeemed to my IB account, I can then transfer them to my external GBP account. The long term plan would be to redeem the funds back to AUD.......but I can wait many years for that. So, this looks like a possible solution for me, thanks!