Some 500,000 women in their late 50s were affected by the decision of the coalition government.
It added up to 18 months onto the start date of their state pension.
Speaking to the BBC's Money Box programme, she said her job was to implement the past government's policy.
Many of the women affected say it has left them trying to bridge the gap at an age where re-entering the labour market is very difficult.
One of those affected was Wendy, who started work in her teens in Manchester and who expected her pension at 60.
"I intended to stay in employment, but that came to an end at 61. I claimed Jobseeker's Allowance (JSA) and so far have applied for almost 4,000 jobs," she said.
She gets £65 a week JSA and has to find £25 from that to go towards her rent.
"Gas and electric take up most of the rest of the money. I am dependent on the generosity of neighbours for food. It is not a position I expected to find myself in," she said.
Baroness Altmann said: "I have so much sympathy for people whose pension age was increased at relatively short notice by up to 18 months.
"I don't have billions of pounds to spend on keeping state pension age unequal for longer.
"My job is to implement the laws that have been properly passed."
The minister claimed that when these women do get their pension they will be on average £8 a week better off on the new state pension.
Campaigners argue that these women will still lose money.
Lin Phillips, who helped found Women Against State Pension Inequality, said: "She's missing the point. We are losing just over £5,000 a year from the pension we have not had. If we had have known we could have prepared for that."
The pressure group wants a transitional payment to tide women like Wendy over the gap between what they expected and what they got.
Baroness Altmann said that was not possible.
"I have been looking at ways in which we might be able to help. I have been looking at it but I can't see any way of doing it," she said.
When asked if she had rejected the idea, she replied: "I haven't rejected anything. I have been looking and I will continue to look but I haven't been able to find anything."
Listen to the full interview on Money Box on BBC Radio 4 at 1200 BST on Saturday 26 September.
Pensions Minister Baroness Altmann has told the BBC she considered helping women who have had the start date of their state pension put back twice, but could not find a way to do so.