From Moscow to Washington to New Delhi and points in between, dismay and condemnation poured forth yesterday over the assassination of Pakistani opposition leader Benazir Bhutto, along with concern for the stability of the volatile region. World leaders lauded her bravery and commitment to democratic reform.

The UN Security Council voted unanimously to condemn the killing and urged all nations to help bring those responsible for “this reprehensible act” to justice.

In India, which has fought three wars against Pakistan, Prime Minister Manmohan Singh said Bhutto was irreplaceable, and noted she had striven to improve relations between the two nuclear-armed countries.

“I was deeply shocked and horrified to hear of the heinous assassination,” Singh said. “In her death, the subcontinent has lost an outstanding leader who worked for democracy and reconciliation in her country.”

In Texas, a tense-looking President George W Bush demanded that those responsible be tracked down and brought to justice.

“The United States strongly condemns this cowardly act by murderous extremists who are trying to undermine Pakistan’s democracy,” Bush told reporters at his ranch in Crawford.

“We stand with the people of Pakistan in their struggle against the forces of terror and extremism.”

He later spoke briefly by phone with Pakistan President Pervez Musharraf, but White House spokesman Scott Stanzel said he had no details.

Afghanistan’s President Hamid Karzai, who met Bhutto earlier yesterday in Islamabad, said he was “deeply pained” by the assassination of “this brave sister of ours, a brave daughter of the Muslim world”.

“She sacrificed her life, for the sake of Pakistan and for the sake of this region,” he said. “I found in her this morning a lot of love and desire for peace in Afghanistan, for prosperity in Afghanistan and … Pakistan.”

In a letter to Musharraf, French President Nicolas Sarkozy called the attack an “odious act” and said “terrorism and violence have no place in the democratic debate and the combat of ideas and programmes”.

Bhutto, a former two-time prime minister of Pakistan, was killed in a suicide attack in Rawalpindi just 10 weeks after she returned to her homeland from eight years in exile. A suicide attack on her homecoming parade killed more than 140 people. The articulate, poised 54-year-old had lashed out at the spread of Islamic extremism as she campaigned for next month’s parliamentary elections.

The United States had been at the forefront of foreign powers trying to arrange reconciliation between Bhutto and Musharraf, who under heavy US pressure resigned as army chief and earlier this month lifted a state of emergency, in the hope it would put Pakistan back on the road to democracy.

UN Secretary General Ban Ki-moon called for “all Pakistanis to work together for peace and national unity”.

The Vatican spokesman, the Rev Federico Lombardi, said Pope Benedict XVI was immediately informed of the “terrible news”.

“One cannot see signs of peace in this tormented region,” Lombardi said.

Sarkozy said Bhutto had paid “with her life her commitment to the service of her fellow citizens and to Pakistan’s political life” and urged Pakistan’s elections be held as scheduled on January 8.

In Britain, where Bhutto had attended Oxford University, Prime Minister Gordon Brown said she “risked everything in her attempt to win democracy in Pakistan and she has been assassinated by cowards who are afraid of democracy”.

“The terrorists must not be allowed to kill democracy in Pakistan, and this atrocity strengthens our resolve that the terrorists will not win there, here, or anywhere in the world,” Brown said.

EU foreign policy chief Javier Solana said the attack “is clearly aimed at destabilising the country”. He beseeched Pakistanis to refrain from violence.

Italian Premier Romano Prodi said he was filled with grief and called Bhutto “a woman who chose to fight her battle until the end with a single weapon – the one of dialogue and political debate”.