As NATO allies converge in Brussels for a key summit, one topic on the agenda will be a potential increase in the number of troops in Afghanistan - a move met with strong opposition by many in Kabul.

The military alliance began considering a troop increase earlier this month after it received a request from army chiefs for more soldiers to help in the fight against the Taliban, NATO chief Jens Stoltenberg said.

The prospect of a troop surge might have drawn considerable support in Brussels and Washington, but in Kabul the situation is different.

"They are thinking of sending soldiers ... They [the soldiers] will not do anything," Sher Mohammad Karimi, a retired four-star general in the Afghan National Army, told Al Jazeera.

"If they are advisers, then it's OK."

Afghan defence ministry spokesman Mohammad Radmanish agreed, saying that local forces needed better equipment and training.

"What we need now is bombing planes and also modern engineering technology," he told Al Jazeera.

Since NATO's combat mission in Afghanistan formally ended in 2014, Taliban attacks have intensified and Afghan military and civilian casualties have risen.

NATO already has more than 13,000 troops in Afghanistan, including around 6,900 US and 500 British military personnel, who are training the Afghan armed forces to eventually take over the country's defence and security. The US has an additional 1,500 soldiers conducting assist missions directly under Pentagon command.

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Stoltenberg has insisted that a potential troop increase would not mean a return to combat operations.

The discussion of a NATO troop increase in Afghanistan comes as Trump considers a plan to send at least 3,000 troops to Afghanistan in an effort to put enough pressure on the Taliban to come to the negotiating table.

According to The New York Times, Trump was expected to make a decision at Thursday's summit in Brussels regarding a troop increase, but that has been delayed after some within the administration expressed concern over sending more troops.

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Some Afghans fear a foreign troop increase by either NATO or the US could actually prolong the war.

"Increasing foreign troops in Afghanistan is like putting more wood on the fire," an Afghan resident told Al Jazeera.

"If they increase troops in Afghanistan that would provoke Pakistan, Iran and Russia. Neighbouring countries would increase their support for the Taliban, and more Afghans will be fighting each other."

In February, General John Nicholson, the commander of US and NATO forces in Afghanistan, told Congress that he would need an extra "few thousand" troops to make gains against the Taliban and break what he called a stalemate against the armed group's fighters.

At the height of the US combat mission, there were an estimated 100,000 troops in Afghanistan.

"I don't think anybody here is under the illusion that [a troop increase] is going to end the war," Al Jazeera's John Hendren, reporting from Kabul, said.

"The Trump administration here is that would bring the Taliban to the bargaining table, but there is a lot of concern in Afghanistan that this surge is really going to be, at best, a half-measure."

'Pay more, do more'

At the Brussels meeting, the alliance is also expected to officially join a US-led coalition against the Islamic State of Iraq and the Levant (ISIL, also known as ISIS) armed group in Iraq and Syria.

The decision is mainly political because all 28 NATO member states are already individually part of the coalition, with some only taking part in support roles.

It comes on the back of pressure from Trump, who has urged NATO members to do more in the fight against ISIL.

Trump is also expected to urge NATO members to increase defence spending to the target of two percent of a country's annual gross domestic product, as they agreed in 2014.

Al Jazeera's James Bays, reporting from Brussels, said that Trump "certainly wants NATO members to pay more and do more".

Only five members currently meet the target: Britain, Estonia, debt-laden Greece, Poland and the US, which spends more on defense than all the other allies combined.

"I think you can expect the president to be very tough on them, saying, 'Look the U.S. is spending 4 percent. We're doing a lot,'" US Secretary of State Rex Tillerson told reporters on Air Force One.

Many are sceptical about this arbitrary bottom line that takes no account of effective military spending where it is needed most. Germany would have to virtually double its military budget and spend more than Russia.

The allies hope the US president will unequivocally state his support for NATO's mutual defence pledge, known as Article 5.