The proposed flat-rate pension is unlikely to be introduced in the near future, the latest word from Parliament suggests.
Lord Taylor of Holbeach told the House of Lords that the changes would not be 'rushed in' and that it was likely to be something for a future Parliament.
His comments come after Pensions Minister Steve Webb launched a consultation in March on the proposals to introduce a flat-rate pension of £140 per week.
If the current Government runs a full term, the next election will not take place until 2015.
Lord Taylor's comments came in reply to Labour's Lord Tomlinson, who said: 'If we have two different levels of state pension - one for existing pensions and one for new pensioners - that is exactly the sort of injustice that, in other circumstances, were it challenged at judicial review, the challenge would be upheld.'
Lord Taylor said the Government would 'clearly seek to avoid such a situation - that is the reason for the consultation'.
'This is a necessary reform and one that needs to be addressed by the Government, which is wanting to take things forward,' he said.
In reply to a question from Liberal Democrat Lord Dykes about a pension with a value of around '£155 at current prices', Lord Taylor said the Government's consultation process set out two options for a 'simpler and fairer state pension'.
He said: 'The media reports of £155-a-week pension are based on speculation of how much the single-tier state pension could be worth if it is introduced in the future.
'No decisions have been made as to how to change the state pensions.'