Taliban, Afghan forces clash near key northern city
The Taliban have launched major offensives targeting government forces since early May when the US military began its final troop withdrawal, and claim to have seized more than 50 of the country's 421 districts.
Many of their claims are disputed by the government, and independent verification is difficult -- especially in areas that frequently change hands.
He said the insurgents have also taken up positions on highways that connect Kunduz city to neighbouring provinces.
On Monday, the Taliban claimed they had captured the Imam Sahib district of the province, the third to be taken in a week.
"We have launched operations around the city," Taliban spokesman Zabihullah Mujahid told AFP.
The Taliban have repeatedly attempted to capture the city, located not far from the border with Tajikistan.
The insurgents briefly held Kunduz twice before -- in September 2015, and again a year later.
The city's location makes it a key transit point for economic and trade exchanges with Tajikistan.
The insurgents claim to have captured several districts in the northern provinces of Faryab, Takhar and Badakhshan, forcing military leaders to strategically retreat from a number of areas.
The defence ministry confirmed that government troops had retreated from several districts but said they aimed to take them back.
The Taliban are now present in almost every province and are encircling several major cities -- a strategy the militants employed in the mid-1990s when they overran most of Afghanistan until they were ousted by invading US-led forces.