Peter Robinson: Greater devolution might not be in Northern Ireland's interests
Granting Northern Ireland greater powers may not bring any significant benefits to the region, the First Minister has warned.
Peter Robinson said devolving matters earmarked for other parts of the UK, such as income tax responsibilities, may not be workable because of our size.
He also told a Westminster select committee, sitting in Belfast, that the Executive was not obsessed with stacking up powers.
Instead, Mr Robinson said politicians had to prove they were capable of handling complex issues.
"We are open to looking at further powers but we are not obsessed by this issue of stacking up more powers," he said.
"I think what we need to do is to prove that we can operate with the powers that we presently have for the very convoluted system, difficult system to operate, that we have in Northern Ireland."
Mr Robinson was appearing before the cross-party Political and Constitutional Reform Committee.
The event coincided with an announcement that powers to vary Northern Ireland's corporation tax rate will be transferred from Westminster. There has also been a debate around devolving greater income tax responsibilities to the regions.
The Smith Commission, which is examining greater devolution to Scotland, has recommended that the Scottish Parliament should have the power to set income tax rates and bands.
However, Mr Robinson said he did not see great benefits from such a move in Northern Ireland.
He added: "We are a region of 1.8 million people. I can't see that we're going to be significantly capable of changing social and economic outcomes in Northern Ireland as a result of any change in the income tax system. If it were so, then I think there would be an argument, but there are cost issues attached to it as well.
"To have the equivalent to the Scottish revenue in Northern Ireland would be fairly costly and I think would outweigh any advantage that there might be of having a separate system."
In recent months debate has centred on English votes for English laws, meaning Northern Ireland MPs could be banned from voting on certain matters.
Ulster Unionist leader Mike Nesbitt said reserving English matters for English MPs was feasible. But he added: "I wouldn't like to see Westminster become a place where you have English MPs, Northern Irish MPs, Welsh MPs and Scottish MPs, and no one is working together for the common good."
SDLP leader Alasdair McDonnell also warned that English-only laws could still impact elsewhere.
"There are very few laws that don't have consequentials," he said.
Alliance Party leader David Ford said he backed the establishment of a federal-type system of government.
The Political and Constitutional Reform Committee was established in 2010 and consists of 11 MPs drawn from across the political parties, both in government and the opposition. SDLP MP Mark Durkan sits on the committee. It is scrutinising the work of Deputy PM Nick Clegg, who is overseeing political and constitutional reform.