US SUPPORT NO "BLANK CHECK"

While reassuring the Afghan government about the US commitment of cooperative work, Trump also warned that the support of the United States was "not a blank check," and its patience was "not unlimited."

"The government of Afghanistan must carry their share of military, political and economic burden," said Trump.

Meanwhile, Trump expressed his open attitude toward the Taliban, voicing a possibility to "have a political settlement that includes elements of the Taliban" someday after an effective military effort.

In his address, Trump also pledged to further develop the US strategic partnership with India, which was a critical part of the South Asia strategy for the United States.

Hailing Trump's speech, Mattis said the president's strategy came after "a rigorous interagency review."

"I will be in consultation with the Secretary General of NATO and our allies -- several of which have also committed to increasing their troop numbers," said Mattis in a statement released by the Defense Department later in the day.

The new Afghanistan strategy comes at a time when senior US officials warned of a dire security situation in Afghanistan.

In a congressional hearing in June, Mattis said that the United States was still "not winning" the longest war in US history in Afghanistan.

Trump delivered the national address after a lengthy meeting with his national security team at Camp David on Friday.

Former US President George W. Bush ordered to dispatch US troops to fight the war in Afghanistan in October 2001, after the 9/11 terrorist attacks.

It has been reported that about 2,400 US soldiers have died in Afghanistan since 2001.