UK-based The Observer, a sister concern of The Guardian, on Sunday reported that human rights groups are demanding that two of Britain's biggest banks explain why they have lent tens of millions of pounds to such a company.
HSBC and Standard Chartered have loaned a total of $60m (£44.5m) to Vietnamese telecom giant Viettel, which has stakes in Myanmar mobile network Mytel, in the last four years.
Over that period, the Myanmar military has been accused of committing war crimes, genocide and crimes against humanity.