Ms Miller told MPs there were "fundamental policy" issues that needed to be considered with "financial implications", such as pension entitlements for heterosexual civil partners, widows and widowers.
And former Labour defence secretary Lord Hutton - the man the government appointed to oversee a review of public sector pensions - said linking the military pension to the consumer price index, rather than the retail price index, would mean war widows and the injured would get smaller payments in future.