Kabul, Afghanistan - An attack that saw the United States drop the largest non-nuclear bomb on Afghanistan was a "brutal act" against Afghan people, the environment and the country's sovereignty, Hamid Karzai, former president, has told Al Jazeera. 
 
 The 9,797kg GBU-43 Massive Ordnance Air Blast (MOAB) was unleashed in combat for the first time on Thursday, targeting a complex of caves and tunnels used by ISIL fighters in Nangarhar province, according to the US army. 
 
 Dubbed the "Mother of All Bombs", the device can devastate the area around its landing of a radius of more than 1.6km. 
 
 "This was an inhuman act, a brutal act against an innocent country, against innocent people, against our land, against our sovereignty, against our soil and against our future," Karzai said in Kabul. 
 
 "A bomb of that magnitude has consequences for the environment, for our lives, for our plants, for our water, for our soil - this is poison." 
 
 WATCH: What impact will MOAB have in the fight against ISIL? 
 
 At least 90 ISIL fighters were killed in the attack, according to the US and Afghan armies. 
 
 For the most part, Afghan officials welcomed the bombing, saying it was a step towards security. They have also said that there were no civilian casualties. 
 
 But Karzai, who was president from 2004 until 2014, said the US should stop using Afghanistan as a "testing ground" and re-engage with Afghans towards a peaceful solution. 
 
 If these conditions are met, he said, "they [US] can stay on - if the Afghan people agree to it. If they continue this militant approach, this heavy-handed military approach in Afghanistan, then, of course, I want them out of the country." 
 
 READ MORE: Condemnation, praise over massive bombing 
 
 The massive bomb was dropped after fighting intensified over the past week and US-backed ground forces struggled to advance in the area. 
 
 A US soldier was killed on April 8 in Nangarhar while conducting operations against ISIL, which stands for Islamic State of Iraq and the Levant, and is also known as ISIS. 
 
 Karzai said he was speaking up because many Afghan officials - some of whom were part of his own cabinet - had endorsed the bombing. 
 
 "I considered it a treason and I stood up against them, and I will continue," he said. 
 
 "This poison will be there for years and years to come. How can we allow our country to be used this way And why? How many [ISIL fighters] have they killed, 100, 200, 300? 
 
 "Why should Afghanistan suffer in such a massive way with a bomb so big, so dangerous that they themselves call it the 'mother of all bombs'. 
 
 Karzai's time in office was at times plagued by accusations from the US of corruption and incompetence. 
 
 Fahim Dashty, a journalist, politician and political analyst, said that Karzai's comments were unlikely to be welcomed by the majority of Afghans, dismissing the former president's rhetoric as an attempt at "heroism". 
 
 "There were lots of problems while he was president of Afghanistan," Dashty told Al Jazeera from Kabul. 
 
 OPINION: Bombs away! Wag that dog! 
 
 "At least for a decade, he was using US bodyguards to protect himself. Now he is talking about pushing the US to leave Afghanistan. This is something people will not believe." 
 
 On the bombing, Dashty said Afghans had little reason not to welcome the attack on ISIL targets. 
 
 "There weren't any reports of civilian casualties in the last attack," he said. 
 
 "It was said that it was targeting ISIL leaders. As much as it targets terrorist groups, I think people will welcome it." ||||| Amin Karim, the spokesman for the main faction of Hezb-e-Islami, a conservative Islamist party with links to the insurgency, said members of his party disagreed with the strike because they believed it was carried out for American domestic political reasons and as a way to send a message to other countries at odds with the United States, rather than strictly to fight terrorism in Afghanistan. 
 
 “The goal of this attack was for beyond Afghanistan — it was for showing American power to North Korea, Syria and some other countries; it was for scaring these countries,” Mr. Amin said. 
 
 At a news conference organized by the Nangarhar governor’s office on Friday, a group of elders from the Achin district, where the bomb was dropped, expressed support for the use of such overwhelming force to eliminate the Islamic State fighters. 
 
 Atta Muhammad Noor, the powerful governor of the northern Balkh Province and a leader of the Jamiat-e-Islami, one of the largest Islamist parties, said he supported the use of the bomb as well as any “crackdown on insurgents and fundamentalists.” 
 
 Mr. Karzai said the people of eastern Afghanistan had expressed concern about Islamic State fighters crossing the border with Pakistan when the threat emerged more than two years ago, but little action was taken then. “They allowed Daesh to come and come, and empty villages of their residents and entrench themselves,” he said, using the Arabic acronym for the Islamic State. “Why did they wait for two years? Why didn’t they stop them then? All the entry points were known.” 
 
 
 
 He added: “The conclusion is that Daesh was a U.S. contractor, like DynCorp, like other U.S. companies, that they used to empty an area of its population and create a cause, create an environment, a psychological environment in which the U.S. can then test its weapon.” 
 
 Mr. Karzai, who has grown more anti-American in recent years despite having come to power with the help of the United States military, had been seen as a quiet opposition figure, albeit one intent on derailing Mr. Ghani’s government.
– Former Afghan President Hamid Karzai is mincing no words in assessing the United States' bombing of an ISIS stronghold with its second-largest non-nuclear device, reports the New York Times: "Shame, shame," he says of current President Ashraf Ghani's admission that his government coordinated the bombing with the Trump administration. "No Afghan with self-respect would do that. He is a traitor, a traitor." Karzai further said he will work toward "ousting the US," and the Times notes that he has grown more vocal in his anti-American sentiment since leaving office—despite having largely come to power on the back of the American military. Karzai is denouncing the bomb to anyone who will listen, telling al Jazeera that "This was an inhuman act, a brutal act against an innocent country, against innocent people, against our land, against our sovereignty, against our soil and against our future." Ghani's office wouldn't respond directly, but said only in a statement that "Every Afghan has the right to speak their mind. This is a country of free speech." The Times finds dissent on the bombing within Afghanistan, with one conservative Islamist party rep dismissing the use of the so-called "Mother of all Bombs" as nothing more than a show of American power for the benefit of the likes of North Korea. A powerful governor, meanwhile, said he was in favor of the MOAB, as well as any "crackdown on insurgents and fundamentalists." But most Afghans will consider the messenger in evaluating Karzai's anti-American comments, a journalist tells al Jazeera: "At least for a decade, he was using US bodyguards to protect himself. Now he is talking about pushing the US to leave Afghanistan. This is something people will not believe."