US top intelligence officers offered a grim assessment of Afghanistan's future, saying that the Taliban were set to "continue to make gains."

"Afghan security forces' performance will probably worsen due to a combination of Taliban operations, combat casualties, desertions, poor logistics support and weak leadership," the director of National Intelligence, Dan Coats, told the US Senate Intelligence Committee.

The US and its NATO allies ended their combat mission against the Taliban in 2014, leaving the field to Kabul troops. Ever since, the US-backed government has been losing ground to the insurgents. Kabul now controls or influences only 57 percent of the country's territory, according to the US estimates.

"Unless we change something... the situation will continue to deteriorate and we'll lose all the gains that we've invested in over the last several years," said General Vincent Stewart of the Defense Intelligence Agency on Thursday.

Kabul still dependent on West

NATO still has about 13,450 troops in Afghanistan, including 6,900 US personnel that provide training and advice to local anti-Taliban forces. Additionally, Washington deployed 1,500 troops to fight the so-called "Islamic State" group and the remaining al-Qaida militants in the country.

US General John Nicholson, the commander of foreign troops in Afghanistan, asked Washington in February for several thousand more soldiers to push back against the Taliban insurgency. NATO has since asked its members to consider sending in more troops.

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However, Afghanistan will "almost certainly deteriorate through 2018, even with a modest increase in the military assistance by the US and its partners," US spy chief Dan Coats said. Kabul would continue to struggle with "its dependence on external support" until it either defeated the Taliban or reached a peace deal with them, he added.

Australia mulls over additional deployment

On Friday, Australian Prime Minister Malcom Turnbull said his country was mulling over additional deployment in Afghanistan.

"We are certainly open to increasing our work there, but we've obviously got to look at the commitments of the Australian Defense Force in other parts of the region, and indeed in other parts of the world," Turnbull told reporters in Sydney.

"It is very important that we continue to work together - we and our other allies in the effort in Afghanistan," he said.

Canberra currently has around 300 soldiers in the central Asian country.

Germany not 'first in line'

NATO Secretary-General Jens Stoltenberg also discussed the issue with German Chancellor Angela Merkel in Berlin on Thursday, ahead of a large NATO summit later in May. Stoltenberg said that increasing NATO's presence would not necessarily mean putting soldiers on the front lines.

Germany's army maintains a contingent of around 1,000 soldiers in Afghanistan. Merkel said there were no concrete plans to send in more German soldiers and added that the Bundeswehr is already playing a key role in safeguarding security.

"I don't believe that we are the first in line to increase our capabilities," she said.

dj/rc (Reuters, AFP)