KABUL - The United States and Britain said on Thursday they would send thousands of troops to Afghanistan to protect and help evacuate civilians, as the Taliban stood poised for their two biggest military victories since they began a broad offensive in May.

In response to the militants' swift and violent advances, the Pentagon said it would temporarily send about 3,000 extra troops within 48 hours to help secure the drawdown of U.S.

Embassy personnel from Kabul.

Britain said it would deploy around 600 troops to help its nationals and local translators get out.

While it is common for the U.S. military to send in large number of troops to evacuate personnel in combat zones, the reinforcements will fly in just weeks before the departure of the last of the U.S.-led international force that has had a core role in maintaining security in the country.

South and west of Kabul, the country's second and third largest cities were on the verge of being seized by the Taliban.

The Islamist group claimed control over Herat close to the Iranian border, and a diplomatic source and a witness said it also appeared close to capturing Kandahar in the south - Afghanistan's second largest city and the spiritual home of the group, which now controls about two-thirds of the country.

Earlier in the day, the Taliban established a bridgehead within 150 km (95 miles) of Kabul,

As the United Nations warned that a Taliban offensive reaching the capital would have a "catastrophic impact on civilians," the United States, as well as Germany, urged their citizens to leave Afghanistan immediately.

Reuters