The London-based organization, Burma Campaign UK, has called on Burma’s government to “immediately publish concrete actions it will take” now that it has signed the declaration.

“The timing of the signing, on the eve of the global summit on sexual violence in conflict being held in London next week, is clearly designed to maximize positive publicity for the Burmese government,” Burma Campaign UK said in a statement.

Burma Campaign UK also insisted that Burma’s government put an end to the impunity that Burma’s military has enjoyed for committing acts of sexual violence. In its statement, the NGO said “There is no single step that will end sexual violence by the Burmese Army, but one of the single most effective steps would be to end impunity. If soldiers or those who command soldiers know they will go to jail if they commit rape, that would be an effective initial deterrent.”

Zoya Phan, campaign manager at Burma Campaign UK, said that although the government’s decision was a much-welcomed step in the right direction, an independent inquiry into the sexual violence committed in Burma’s conflict zones is what Burma really needs. “We welcome the Burmese government signing the UN sexual violence declaration, but signing alone is meaningless without an immediate action plan for implementation. This is just a first step on a very long road,” she said.

Zoya Phan cautioned that Burma’s government had made commitments before which have not been fulfilled. “Just because Burma signed the international declaration on sexual violence, it doesn’t mean they will do anything about it. There should be a six-month deadline for seeing implementation of the declaration in Burma. Foreign Secretary William Hague deserves a lot of credit for helping to persuade the Burmese government to sign this declaration, but he should remember Thein Sein’s broken promise on releasing all political prisoners and keep up the pressure to make sure he keeps his word this time,” said Ms. Phan.

A January 2014 report produced by the Women’s League of Burma (WLB)—an umbrella group representing 13 Burma-focused ethnic women’s organizations—documented more than 100 cases of military-perpetrated sexual violence over the past four years, with victims as young as eight years old. Among the cases documented in WLB’s report, 47 women were gang raped and 28 were either killed or died from their injuries.

The WLB report also said that sexual violence is part of a strategy used deliberately by Burma’s army: “These crimes are more than random, isolated acts by rogue soldiers. Their widespread and systematic nature indicates a structural pattern: rape is still used as an instrument of war and oppression.”

Burma Campaign UK insists that high-ranking military officers should be held accountable for these sexual crimes— including the president himself, U Thein Sein. In its statement, the London-based NGO said that “Under international law, when rape and sexual violence is committed in conflict, the commanders of those soldiers committing rape can also be held legally accountable. This accountability should go right to the top and include the head of the army, and the head of state, currently President Thein Sein.”

Burma is the 150th country to sign the “Declaration of Commitment to End Sexual Violence,” an initiative launched last September by UK Foreign Secretary William Hague and the UN’s Special Representative on Sexual Violence in Conflict, Zainab Bangura.