The secretary of state for Northern Ireland is still an important job, according to the Conservative Party's Northern Ireland spokesman.
Owen Paterson is the shadow Northern Ireland secretary
Owen Paterson told the BBC's Inside Politics he would oppose any early merger of the Northern Ireland Office with the Scottish and Welsh offices.
The secretary of state could play an important role after the devolution of policing and justice powers, he said.
"It is important there is a voice for Northern Ireland in the Cabinet."
"I think there have been such gains not just for the province but for the entire United Kingdom and the Republic in what's happened here in recent years - it is all too precious to risk losing," he said.
Devolution was restored to Northern Ireland last May after being suspended for almost five years.
In June, the Northern Ireland Office was reduced to just two ministers following a Cabinet reshuffle.
Northern Ireland Secretary Shaun Woodward has said he believes responsibility for policing and justice will be devolved by the end of this year, a claim rejected by the DUP.