"The main focus of Operation Mansouri will be on foreign forces, their military and intelligence infrastructure and in eliminating their internal mercenary apparatus", it said.
Apparently foreshadowing the spring offensive, a Taliban attack earlier this week on an army base in northern Afghanistan was among the most devastating ever in the country, killing more than 140 Afghan soldiers.
The annual spring offensive normally marks the start of the "fighting season", though this winter the lull was shorter and the Taliban continued to battle government forces.
Fighting has been fierce as US and Afghan special operations forces, backed by hundreds of air strikes, have sought to advance against militant strongholds in recent months.
Three attackers then detonated suicide vests while others used guns and grenades in the deadliest attack on armed forces in the country since 2001.
He said the Afghan forces are committed to any kind of sacrifices to ensure peace and stability for the people of Afghanistan.
Two US service members were killed and another was wounded Thursday while conducting a joint US-Afghan raid in the Achin District of Nangarhar Province, Pentagon spokesman US Navy Capt. Jeff Davis told CNN.
Last Friday's Taleban assault on the military base fuelled fears over insider attacks - when Afghan soldiers and police turn their guns on their colleagues or on global troops - have been a major problem during the war.
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The report said that as of March this year, 210 children had been killed - up 17 percent from the same period last year.
Bullet holes are seen on the wall of a mosque at the military headquarters where the Taliban attack occurred last week in Mazar-i-Sharif, northern Afghanistan April 25, 2017.
'Another tough year' The Taliban announcement comes days after Pentagon chief Jim Mattis visited Kabul as the Trump administration seeks to craft a new strategy in Afghanistan.
Taliban spokesman Zabihullah Mujahid announced the launch of the offensive in an email statement boasting about Taliban's control over more than half of the country, quoting a report issued by Washington's special inspector general for Afghan reconstruction in February.
"I believe this will be a hard year for Afghan security forces, as they will be facing the resilient Taliban's complex and sophisticated attacks countrywide", he told AFP.
The troops were working with partnered Afghan soldiers in the raid against ISIS Khorasan, a local offshoot of the jihadist group based in Iraq and Syria.
It was the first time the United States military's GBU-43/B Massive Ordnance Air Blast, dubbed the "Mother of All Bombs" had been used in combat. Some analysts even argued the strike could boost the Taliban, who had been fighting a turf war with IS in Nangarhar province near the border with Pakistan, where the bomb was dropped.
President Trump has ordered a review of the US policy in Afghanistan.