U.S. lawmakers this week will be in the curious position of sparring not only over a new 2012 budget proposal - Republicans are set to propose dramatic changes to Medicaid and Medicare - but also over a plan for 2011 spending, which was never settled. If a 2011 plan isn't agreed to by the end of the week, a partial government shutdown could ensue. Here is a look at this and some of the other stories CNN plans to follow this week:

Friday is deadline for 2011 spending plan

Less than six months remain in the U.S. government's fiscal year 2011, and Congress still hasn't passed a spending measure that would cover the whole thing.  That could change by Friday, when the most recent temporary measure expires.

Republicans have long been pushing to cut spending by $61 billion, but Democrats generally wanted only a fraction of that. Negotiators agreed tentatively last week on a compromise to slash $33 billion in federal spending, but there were disagreements over where to cut, and some House Republicans indicated they wouldn't go along, arguing $33 billion isn’t enough. If a full 2011 plan (or another temporary spending measure) isn't passed by Friday, some government services and offices could shut down until a plan is agreed upon.

House Republican to propose big changes to Medicaid, Medicare

While lawmakers sort out 2011 spending, the House budget chairman is set to unveil a 2012 plan that would impose deep cuts to Medicaid and big changes to Medicare in an effort to save more than $2 trillion in a matter of years.

U.S. Rep. Paul Ryan, R-Wisconsin, expects to unveil his plan on Tuesday. Sources said his plan would cut Medicaid spending by up to $1 trillion, and he told Fox News on Sunday that his overhaul for elderly health care would - starting in 10 years - give seniors money to help pay for health insurance premiums rather than enroll them in Medicare. GOP sources said that the plan would save hundreds of billions of dollars more than President Barack Obama's 2012 budget proposal, and trillions over the next 10 years.

Workers trying to stop leak of radioactive water from Japanese power plant

Workers responding to a weeks-long crisis at Japan's Fukushima Daiichi nuclear power plant are trying to plug a crack that officials say is leaking highly radioactive water into the Pacific Ocean.

The struggle is part of a larger effort to prevent the further release of radioactive material and keep nuclear fuel cool following a March 11 earthquake and tsunami that led to numerous explosions and the failure of the reactors' cooling systems.

Authorities found water gushing into the sea from a crack in a concrete-lined basin behind one the damaged reactors' turbine buildings. Workers so far have tried to plug the crack with a chemical compound mixed with sawdust and newspaper, but so far it hasn't done the trick. Officials believe the water spewing from the crack is one source of alarmingly high radiation going into the ocean.

More peacekeeping troops head to Ivory Coast

A fierce battle for the Ivory Coast city of Abidjan appears to loom as backers of the country's internationally recognized president seek to oust the incumbent who has refused to leave office.

Fighting already erupted last week in parts of Abidjan between forces of Alassane Ouattara and those loyal to Laurent Gbagbo. The international community recognized Ouattara as the winner of a November election, but Gbagbo has refused to step down.

French has sent 300 more peacekeeping troops to the country, bolstering a United Nations peacekeeping mission of about 7,500 troops. Meanwhile, the United Nations is looking into reports of a massacre last week in the Ivory Coast town of Duekoue as Ouattara's forces advanced.  A U.N. official says 330 people were killed, blaming 220 deaths on pro-Ouattara forces and 100 on pro-Gbagbo forces. But the International Committee of the Red Cross says 800 were killed, and that most of them were civilians.

Libyan fighting continues as government spurns cease-fire proposal

Notions of a cease-fire in Libya between pro-government forces and rebels have faded as battles for control of certain cities continue. Last week, a Libyan opposition leader laid out cease-fire conditions including freedom of expression for the Libyan people and the removal of snipers, mercenaries and militias from western cities, but the government spurned the offer.

Rebels are seeking an end to Moammar Gadhafi's nearly 42-year rule, and an international coalition now led by NATO has been enforcing a no-fly zone authorized by a U.N. Security Council resolution. British diplomats have met with opposition figures in Libya, but Western allies have made no decision on whether to arm the rebels, the U.K. foreign office said Sunday.

Unrest continues in Yemen, Syria

Violence continues to surround protests in Yemen, where tens of thousands of demonstrators for weeks have demanded the removal of longtime President Ali Abdullah Saleh. Calls for his removal have intensified following revolutions earlier this year in Tunisia and Egypt and more than 800 people were injured Sunday when Yemeni security forces attacked protesters in Taiz, a field hospital said.

Saleh has offered to step down by the end of the year, after constitutional reforms and elections. But the country's largest opposition bloc has demanded his immediate removal, and its latest transition proposal was rejected over the weekend by Yemen's parliament speaker.

In Syria, whose president also faces protests, opposition leaders are saying that if certain demands are met, they won't call for the regime's collapse. The demands include the immediate release of political prisoners, lifting of emergency and martial laws and withdrawal of intelligence forces from Syrian cities.

The protests are part of a wave of unrest that has swept Middle Eastern and North African countries this year. Check this page for a roundup and explanations of unrest in these nations.

Documents on James Earl Ray to be released

On Monday, 43 years to the day that the Rev. Martin Luther King Jr. was assassinated in Tennessee, a county government will release recently discovered photos and letters relating to the man convicted of killing him.

Officials in Shelby County, Tennessee, will release the documents, which provide a new look at James Earl Ray.

The documents, discovered five years ago in an archival building, include photos of Ray just after he was incarcerated and letters to his family and his attorney during the eight months he was detained at the Shelby County jail.

King was fatally shot in April 1968 as he stood on a balcony of the Lorraine Motel in Memphis. Ray pleaded guilty to the murder of the civil rights leader and was sentenced to 99 years in prison; he died in 1998.

The documents are to be released Monday on a Shelby County website.

NCAA basketball championship on Monday

Last year, Butler came within one shot of an NCAA men's basketball title. On Monday, they'll give it another go, facing a Connecticut squad that will try to give coach Jim Calhoun his third national championship. SI.com's Luke Winn profiles both teams and wonders which team is the underdog.