Updated: 5:43 p.m.

With debate over President Barack Obama’s latest emergency war spending request on the horizon, two anti-war Congressional Democrats are planning to introduce proposals next week that could highlight Democratic divisions over whether Congress should impose timetables for withdrawing troops from Afghanistan.

Sen. Russ Feingold (D-Wis.) and Rep. Jim McGovern (D-Mass.) are planning to introduce companion proposals that would call for a “flexible timetable to draw down U.S. troops from Afghanistan,” a Feingold aide confirmed Thursday.

In advance of that move, Feingold and McGovern joined with Rep. Walter Jones Jr. (R-N.C.) in penning a letter to Obama Thursday voicing concern about the administration’s Afghanistan strategy and to calling on Obama to act on his own to set a timetable for troop withdrawal that — while flexible — would “clearly specify any variables that would warrant its alteration.”

“Setting a timetable for the orderly withdrawal of U.S. troops does not mean ceasing our engagement in Afghanistan and the region,” the lawmakers wrote. “Our continued commitment to assist the people of Afghanistan will remain important in supporting the emergence of responsive and capable government institutions that can address the socioeconomic and political issues destabilizing the country. However, we need to recognize that corruption and lack of legitimacy in the Afghan government make our current approach unlikely to succeed.”

Jones, an Armed Services member and a former Democrat whose district includes Camp Lejune, has been one of the most vehement Republican critics in Congress of the Iraq War and has also been vocally opposed to Obama’s plans for a troop surge in Afghanistan.

Obama’s $33 billion supplemental request to help pay for the buildup of U.S. troops in Afghanistan is expected to be among the major items on Congress’ plate when Members return to Washington next week. Military leaders have indicated they will need the additional funds by Memorial Day to help pay for the escalation of more than 30,000 troops in Afghanistan that Obama ordered in early December.

McGovern plans to introduce his bill next week, spokesman Michael Mershon said. Mershon added that his boss “will be looking for opportunities to offer it,” but hasn’t had any discussions with leadership about potential vehicles yet.

Feingold and McGovern’s proposals could signal a hardening stance on the part of anti-war Democrats in Congress, many of whom have not pressed Obama particularly hard to end U.S. military involvement in Afghanistan during his first year in office. Rep. Dennis Kucinich (D-Ohio) offered a privileged resolution last month that, if successful, would have subjected Obama to a 30-day deadline to withdraw U.S. troops from Afghanistan. The measure drew just 65 votes, including from five Republicans.

It remains to be seen whether Feingold and McGovern’s proposals will galvanize liberal House Democrats, who were united in their opposition to the Iraq War but have been somewhat divided on Obama’s Afghanistan strategy.

Only about half of the 80-plus members of the Congressional Progressive Caucus supported Kucinich’s resolution last month. The caucus’ co-chairmen — Reps. Raúl Grijalva (D-Ariz.) and Lynn Woolsey (D-Calif.) — both supported the resolution.

As part of his fiscal 2011 budget, Obama requested an additional $159.3 billion for ongoing military operations in Iraq and Afghanistan. Top National Guard and Army Reserve officials are slated to testify April 14 before the House Appropriations Subcommittee on Defense at a hearing on the National Guard and Army Reserve readiness.