WASHINGTON >> President Barack Obama turned to former Secretary of State Colin Powell for help Wednesday in getting a stalled nuclear weapons treaty with Russia through the Senate.

Obama invited the retired four-star Army general and former Joint Chiefs of Staff chairman to the White House a day after stressing the need for the Senate to ratify the New START treaty by the end of the year.

The president has said the treaty is crucial to U.S. national security, and he appealed anew for its approval Tuesday in a meeting with bipartisan congressional leaders. But leading Republican lawmakers argue that there are more pressing priorities to address during the lame-duck session of Congress and the GOP has threatened to block any Senate floor business other than budgetary or tax issues during the lame duck session.

However, some Republicans appear to be leaving the door open for ratification, indicating that the administration has addressed some of their concerns, including several matters raised by Sen. Jon Kyl, R-Ariz., about modernization of the remaining nuclear arsenal and sufficient funds for safeguarding the stockpile.

A pledge by Senate Republicans Wednesday to thwart action on all legislation until lawmakers vote to fund the government and prevent looming tax increases technically does not apply to the START. Treaties have special status, and Republicans can’t block Senate Majority Leader Harry Reid from bringing START to the floor.

Powell is the latest in a string of current and former national security officials brought in to bolster the need to ratify the treaty.

Last month, Obama met at the White House with what he called “some of the most able statesmen from both parties” to voice their support for START. They included former secretaries of state Madeleine Albright, James Baker III and Henry Kissinger, former defense secretaries William Perry and William Cohen and former National Security Adviser Brent Scowcroft.

During a NATO summit in Portugal, Obama also secured the backing of several Eastern European nations, which appeased some Republicans, including Sen. George Voinovich, R-Ohio, who had said he was concerned the treaty would undermine the confidence of allies in Central and Eastern Europe.

Powell served as secretary of state under former President George W. Bush. Since leaving the government, Powell has worked on education issues, which the White House said he would also discuss with Obama.