The United States has long-term interests in Central Asia and will support the sovereignty and integrity of regional states, U.S. Assistant Secretary of State for South and Central Asian Affairs Nisha Biswal said on Friday.

She promised further assistance for the strengthening of Tajikistan's border with Afghanistan.

The United States takes seriously regional problems such as terrorism, extremism and drug trafficking, and participates in their deterrence, Biswal said in an online conference with Tajik reporters organized by the U.S. Embassy in Dushanbe. She was in Washington DC at the moment of the conference.

She reiterated U.S. long-term interests in the region and the attention they were giving to the independence, sovereignty and integrity of the Central Asian states. All Central Asian countries have been U.S. partners for 24 years and the United States feels optimistic about the future of this partnership, she said.

The United States backs the CASA 1000 Electricity Transmission and Trade Project for Central Asia and South Asia in which Afghanistan and Pakistan will import electricity from Tajikistan and Kyrgyzstan, and pledges to carry on assistance for the strengthening of Tajikistan's border, Biswal said.

The United States is closely interacting with the Afghan army in bolstering its capacities and cooperation is also underway with the Tajik government, Biswal said.

The United States will keep working on border security and support security in Afghanistan, she added.