In something of a reverse from his campaign pledges, President Donald Trump has committed the United States to an open-ended conflict in Afghanistan, signalling he would send more troops as he vowed "a fight to win".

In a speech on Monday, Trump promised to step up a military campaign against the Taliban and said the US would shift away from a "time-based" approach.

He also singled out Pakistan for "harbouring" elements of the Taliban and said he was hoping for eventual peace talks with the armed group.

The speech came after a months-long review of US policy.

READ MORE: Timeline - US intervention in Afghanistan 2001 to 2017

Al Jazeera spoke to Hamdullah Mohib, the Afghan ambassador to the US, on the reaction from Kabul.

Al Jazeera: Is this what you expected to hear from President Trump?

Hamdullah Mohib: Yes, we welcome this decision. It was a result of intense deliberations that took into account both of our countries' needs and considerations.

It's the first time that such a tremendous amount of focus has been put on Afghanistan to succeed and we are grateful for this outcome.

Al Jazeera: What do you think Trump meant when he focused on needs and conditions instead of timelines? From an Afghan perspective, what are those needs and conditions?

Mohib: For too long, we focused on predetermined numbers and timelines, without taking into account that perhaps the war doesn't go with those kind of plans. There would be times where we needed more support, and there had been other occasions where that support may not be as critical.

But because the numbers were defined, the enemy always knew what they could expect, and for how long they needed to be patient and adjust their policy.

What we wanted was to move away from the discussion about predetermined troop numbers, and predetermined timelines, to move to a circumstance where the situation on the ground dictates what kind of military support is required.

Al Jazeera: Trump called Pakistan a "terrorist" haven. What do you make of those comments?

Mohib: We welcome the breaking of the silence over Pakistan sheltering and providing sanctuary to terrorists.

For far too long, Afghans have been pointing to the sanctuaries across the Durand Line in Pakistan, and all of the logistical and military support provided to those terrorists who have been targeting both Afghans and our partners, including the United States, in Afghanistan.

I think [it is] a great shift in strategy that will lead to more stability in Afghanistan.

Al Jazeera: Would you say Trump outlined a political strategy in his speech?

Mohib: It's an integrated policy of America's military, economic and political power to achieve our shared goals. So yes, this was more a political policy than it was a military policy.

It laid out that there will be focus on reforms in Afghanistan. We have been working with our counterparts on what needs to be done, on our part, and what needs to be done on the American part.

What we've seen now is America's commitment to continued support to the Afghan security forces, but not just that. It also takes into account regional diplomacy and ensures that we invest in Afghanistan's economic potential so that we become self-reliant on every front, politically, economically and militarily.