Ameritrade is available internationally. Do you mean, Ameritrade has confirmed that the zero commission will not apply to international clients?
https://start.tdameritrade.com/open
"What you need:
- Social Security Number or ITIN
- Foreign tax ID, passport, or visa number (if you're not a U.S. citizen or permanent resident)
- ..."
Internationally is a meaningless term. The question is residents of what non-US countries are accepted as customers. The list can be as small as one country.Schwab could be the winner as Ameritrade and IB lite are not available internationally.
www.schwab.co.uk