US President Barack Obama's new envoy to Afghanistan met with President Hamid Karzai on Saturday amid a downturn in US-Afghan relations and an upswing in violence. Karzai says he still has not spoken with Obama almost a month after his inauguration, a sign the Afghan president no longer enjoys the favored status he had under former US President George W. Bush. "There is tension between us and the US government on issues of civilian casualties, arrests of Afghans, nightly raids on homes and the casualties they cause," Karzai told al-Jazeera television in an interview Friday. Obama has said the US will increase its attention on Afghanistan under his tenure as the US transitions out of Iraq. But the administration is still debating how to stem the rising Taliban tide and tackle the endemic corruption in Karzai's government more than seven years after the 2001 invasion.