WASHINGTON — The next time the president goes to war, Congress should be consulted and vote on whether it agrees, according to a bipartisan study group chaired by former secretaries of state James Baker III and Warren Christopher.

In a report released yesterday, the panel says the current law governing the nation’s war powers has failed to promote cooperation between the executive and legislative branches. It says the 1973 resolution should be repealed and replaced with new legislation that would require the president to inform Congress of any plans to engage in “significant armed conflict,” or non-covert operations lasting longer than a week.

In turn, Congress would act within 30 days, either approving or disapproving the action.

Mr. Baker, who served as secretary of state in the first Bush administration and co-chaired the 2006 Iraq Study Group, said the proposal isn’t intended to resolve constitutional disputes between the White House and Congress on who should decide whether the nation fights.

“What we aim to do with this statute is to create a process that will encourage the two branches to cooperate and consult in a way that is both practical and true to the spirit of the Constitution,” Mr. Baker said in a statement.

A new joint House and Senate committee would be established to review the president’s justification for war. To do so, the committee would be granted access to highly classified information.

The panel has briefed the presidential campaigns of senators Obama and McCain, as well as congressional leadership.

A spokesman, Tommy Vietor, said Mr. Obama commends the panel “for advocating that the president consult Congress more closely on issues of critical national importance like the use of military force.”

Mr. McCain did not provide comment.

Congress’s involvement in approving combat operations became a central issue in the Iraq debate last year, when Democrats tried to force President Bush to end the war. While Congress had authorized combat in Iraq, Democrats said the resolution approved only the invasion and not a five-year counterinsurgency.

After taking control of Congress in January 2007, Democrats tried to cap force levels and set a timetable for withdrawals. While they lacked a veto-proof majority to put the restrictions into law, the White House argued that such legislation would have violated the Constitution by infringing upon the president’s right as commander in chief to protect the nation. Democrats disagreed, contending there was ample precedence.

The one surefire way for Congress to have ended the war was to cut off money for combat operations — a step most Democrats weren’t willing to take because they feared doing so would have hurt troops in harm’s way, or at least be perceived by voters that way.

The plan identified by Baker and Christopher, who served as secretary of State under President Clinton, would not necessarily resolve such issues in the future. But it would create a consultative process between the White House and Congress that currently does not exist. Also, calling on Congress to respond would exert significant political pressure on a president if he ignored lawmakers’ wishes.