Uruguay's ruling coalition insisted on holding a vote in Congress Thursday to annul an amnesty that has protected officials of this country's former military dictatorship from being prosecuted for crimes against humanity.

The measure has deeply divided this small and politically moderate country of 3.5 million people, where memories of the 1973-1985 military government remain fresh.

Controversy over the move to annul the amnesty has harmed President Jose "Pepe" Mujica's popularity, raised questions about how the military will respond and threatened the future of the "Broad Front" government, a coalition of parties, unions and social organizations that range from centrist to communist.

The Supreme Court ruled the amnesty unconstitutional in 2009, but voters have upheld the law twice in popular referenda. Mujica has warned the head of the "Broad Front" coalition that annuling the amnesty would create "political dangers that may be impossible to overcome."

Mujica, a leftist former Tupamaro guerrilla who spent the dictatorship behind bars, has also said he wouldn't veto the measure if it passes the lower house of Congress, where the ruling coalition has a 50-49 seat majority. The Senate approved it by a single vote in April, with Vice President Danilo Astori casting the deciding ballot, and the measure had appeared likely to pass the lower house this week.

On Wednesday, everything seemed to depend on one man — Broad Front Deputy Victor Semproni, who said he would block the annulment measure by refusing to vote.

Mujica's wife, Sen. Lucia Topolansky, warned Semproni that doing so despite the clear wishes of the coalition's leadership would amount to political suicide. "Don't immolate yourself," she said.

But Semproni told The Associated Press that he's insisting on following the will of the people over his party.

Military veteran groups have denounced the plan to overturn the 1986 amnesty for soldiers while leaving intact a similar amnesty protecting leftist guerrillas.

The twin measures helped a then-fragile democracy rebuild after 12 years of dictatorship. But calls for prosecuting crimes against humanity have increased in recent years.

A peace commission found in 2003 that the dictatorship killed 175 leftist political activists, 26 of them in clandestine torture centers. But abuses were committed by both sides. The Tupamaros began their armed uprising in 1963 against democratically elected governments and were responsible for dozens of killings, kidnappings, robberies, arsons and other attacks before they were defeated a decade later.

Both plebiscites to overturn the amnesty failed to win majorities, getting 46 percent support in 1989 and 48 percent support in 2009. And even with the high court's ruling, Uruguay has mostly prosecuted crimes that were beyond the amnesty's scope, such as murders committed outside the country. About a dozen former officials have been imprisoned.

The Inter-American Court of Human Rights ruled this year that Uruguay must stop putting up roadblocks to prosecuting crimes against humanity.

Pollsters, meanwhile, say Mujica's seemingly ambivalent handling of the case is responsible for his recent drop in support to 41 percent. Mujica blamed his own foreign minister, Luis Almagro, for sending the measure to Congress.

Military veterans and officials have been outspoken in opposing the anullment. Since the return of democracy, the military has been firmly under civilian control.

"It's clear now what kind of morality moves our enemies. It's profoundly immoral, antidemocratic," said retired Col. Jose Carlos Araujo, spokesman for the Liberty and Harmony forum of former military officials, following the measure's passage in the Senate. "They don't even respect the decisions of the people."

In a symbolic move, the commanders of all three military branches appeared Wednesday at what is usually a low-key annual memorial for four soldiers who were killed by Tupamaros in 1972.

Mujica appeared at a separate ceremony Wednesday, honoring the battle 200 years ago that led to Uruguay's independence from Spain. He urged Uruguayans to seek their usual political consensus.

"You cannot overcome (problems) with hate," Mujica said. "The only way you can overcome is by being better judges of ourselves and a bit more indulgent with others. We cannot trasmit the frustrations of the past to new generations of soldiers."


AP staff writer Michael Warren contributed to this story from Buenos Aires, Argentina.