Divisions at the top of Afghanistan’s government deepened on Tuesday after President Ashraf Ghani was forced to reject accusations by his own vice president that he was favouring members of his Pashtun ethnic group. Ghani’s reaction followed incendiary comments from First Vice President General Rashid Dostum, an ethnic Uzbek with a long history of blunt speaking and a sizeable militia at his command, who said the government was wholly run by Pashtuns. “Anyone who speaks Pashto is a good man,” Dostum said at a press conference in the northern province of Faryab. “If he speaks Pashto and is from Logar, he is even a better person,” he added, referring to Ghani’s home province in eastern Afghanistan. Dostum accused a small Pashtun coterie around the president, including National Security Adviser Hanif Atmar, intelligence chief Massoom Stanekzai and chief of staff Abdul Salam Rahimi, of controlling Ghani. “If they say the milk is black, the president says the milk is black,” he said. The comments, which risk stoking brewing ethnic tensions, were made last week but only gained wide attention after they circulated on social media. Pashtuns are Afghanistan’s largest ethnic group and have always dominated Afghan governments. But resentment of their dominance has been growing among others, including Persian-speaking Tajiks and Hazaras and Dostum’s Uzbek minority. In a statement on Tuesday, Ghani rejected the comments, which he said helped Afghanistan’s enemies and were not consistent with Dostum’s position in the government. In a comment that appeared to reflect accusations against Dostum of widespread human rights violations, the statement also said that the government “was aware of its duty” and could investigate complaints of abuses and crimes “by the Taliban and any other forces involved in the fighting”. The spat comes at a difficult moment for the unwieldy national unity government, which has been riven by infighting and has struggled to contain an escalating Taliban insurgency. The militants have come close to seizing at least three provincial capitals in recent months, pushing into Kunduz in the north, Lashkar Gah in the southern province of Helmand and Tarin Kot in the southern province of Uruzgan. Heavy casualties were inflicted, laying bare the weakness of Afghan security forces. As the security situation has deteriorated and political divisions worsened, old rivalries between Afghanistan’s different ethnic groups have resurfaced, threatening the stability of the Western-backed government. Ghani, a former World Bank official, is supported by the United States, which sees him as the leader most committed to fighting corruption and reforming the shattered economy. But political rivals accuse him of monopolizing power, while many non-Pashtuns believe he deliberately favours his own ethnic group at the expense of others.