BRUSSELS: They remembered him as “The Bulldozer” – a US diplomat with such a forceful persona he could drag politicans, military brass and even warlords to the negotiating table in a quest for peace. World leaders Tuesday praised US envoy Richard Holbrooke for engineering the end of the 1992-95 Bosnia war – Europe's bloodiest conflict since World War II – and for seeking to bring stability to war-torn Afghanistan. Even Holbrooke's main opponent in the war in Bosnia, Bosnian Serb leader Radovan Karadzic, expressed “sadness and regret” over Holbrooke's unexpected death Monday following surgery for a tear in his aorta. Karadzic had been hoping to call Holbrooke to testify in his genocide trial. NATO Secretary General Anders Fogh Rasmussen paid tribute to Holbrooke's legendary diplomatic skills, saying he played an essential role in the 1995 Dayton Agreement that ended the Bosnian war and lauding his work in Afghanistan. As President Barack Obama's special envoy to Afghanistan, Holbrooke realized “that we sometimes have to defend our security by facing conflicts in distant places,” Fogh Rasmussen said. Afghan President Hamid Karzai and Pakistani leader Asif Ali Zardari also praised Holbrooke, who died at 69, though Holbrooke's style did not play as well with Karzai as it did with Balkan leaders. Aides said Karzai considered the US envoy ignorant of Afghan culture. Perhaps as a result, Holbrooke played a less visible role in Afghanistan, with Sen. John Kerry taking the main role in convincing Karzai to agree to a runoff election in 2009. “We will always remember ... his efforts for promoting peace and stability in our region, with a deep sense of appreciation and gratitude,” Pakistani Prime Minister Yousaf Raza Gilani said in Islamabad. German Foreign Minister Guido Westerwelle said the world should be grateful to Holbrooke for his contribution to the international strategy in Afghanistan. “We regret with all our heart that he will not be able to witness the success of the new strategy,” Westerwelle said in Brussels. Holbrooke earned the nickname “The Bulldozer” after he bullied warring Serbs, Croats and Muslims to agree to end the Bosnian war with sometimes risky diplomatic overtures. Swedish Foreign Minister Carl Bildt, who served as an envoy to Bosnia in the early 1990s, said the strategy gave Holbrooke many close friends but also many enemies. Bildt described Holbrooke as “truly a giant among diplomats of our time,” and “one of the best and the brightest.” British officials also offered tribute. “He will always be remembered for his preeminent role in ending the vicious war in Bosnia, where his force of personality and his negotiating skill combined to drive through the Dayton peace agreement and put a halt to the fighting,” British Prime Minister David Cameron said in London. Not all Bosnians admired Holbrooke's efforts to achieve peace, arguing that the multiethnic state he set up as part of the Dayton peace process had proven too unwieldy for effective governance. “He was instrumental in bringing peace to Bosnia. An unjust peace, but still a peace,” said Haris Silajdzic, Bosnia's wartime foreign minister who participated in the Dayton negotiations.