MPs could be given the final say on international treaties under new measures put forward by the government.
Under Gordon Brown's plans for constitutional reform, parliament would also gain the final right to declare war, wresting the royal prerogative from the government.
Ministers today set out a consultation on how the role of parliament could be strengthened regarding decisions to declare war, deploy troops or ratify troops.
The government wants to make it a statutory requirement to put treaties to both houses before ratification.
Foreign secretary David Miliband said it marked an important step in Mr Brown's commitment to consulting on prerogative powers.
Pointing to the far-reaching impact of international treaties, Mr Miliband said it was right to ask how MPs could have a guaranteed role in scrutinising new treaties. Today's consultation will consider how MPs could trigger a vote.
The consultation will also consider whether MPs should have a greater say over the decision to go to work. Currently the prime minister holds the prerogative power and does not need parliament's formal approval to deploy troops.
Defence secretary Des Browne said: "There are few greater responsibilities for a nation than to commit its troops to war.
"It's right that our service personnel know they have the backing of the country when they go to war."
As Mr Brown pledges to move forwards with his plans for constitutional reform, first set out in July, the government published two further consultations today.
Justice secretary Jack Straw has launched a consultation on the government's role in appointment judges, asking whether ministers should weald more influence or have their input further limited.
At present, the Judicial Appointments Commission selects judges and the lord chancellor has limited ability to reject or request applicants.
Mr Straw: "Any system must be devoid of party politics, accountable, enhance the integrity and independence of the judiciary, and inspire public confidence. I have every confidence that this new system already achieves this.
"But it is appropriate that in the context of the Governance of Britain debate inaugurated by the prime minister on July 3 we should now seek views on whether any future changes are required."
The government is nominally discussing the possibility of greater involvement for MPs in approving judges. However, it makes clear it has "serious reservations" about adopting US-style confirmation hearings.
Ministers also announced a review of the Freedom of Information (FoI) Act, as Mr Brown promised a cultural change towards a more open government.
A consultation has been opened on whether the FoI should be extended to other organisations that perform public functions.
As part of the process, ministers are also reviewing the "30-year rule," which could reduce the length of time before official documents are passed to the National Archives.