Herald reporter Patrick Gower went to Afghanistan with the war in one of its most critical - and violent - phases. Countries around the world are questioning their involvement - and the New Zealand Government is about to decide what our contribution will be.

Brendon Whitmore is one of 155 New Zealand soldiers in Afghanistan. Inset: US ambassador Ivo Daalder. Photos / Patrick Gower, supplied

Brendon Whitmore is one of 155 New Zealand soldiers in Afghanistan. Inset: US ambassador Ivo Daalder. Photos / Patrick Gower, supplied

The United States is putting pressure on New Zealand to contribute more to the war in Afghanistan, warning Wellington that it should act as an ally in case it ever needs US military support.

President Barack Obama's new ambassador to Nato, Ivo Daalder, has told the Herald that New Zealand should be fighting the Taleban as a "partner and ally" in a Western effort.

Prime Minister John Key has indicated the elite SAS combat troops will be sent back to the war and the United States already has a likely role ready for them.

New Zealand currently has 155 troops in Afghanistan, mainly in a provincial reconstruction team in the relatively stable Bamiyan province.

It also contributes $7 million in aid and a small team of police trainers.

Dr Daalder said the US wanted more troops - in particular the elite SAS - more aid, more police and army trainers as well as civilians with expertise. All would help to bring an end to the war, he said.

"Every penny, troop and trainer will hasten this."

Mr Key has said New Zealand's rationale for being in the war is to counter global terrorism. But Dr Daalder made it clear a major reason for a resumed troop commitment would be the maintenance of military relations with the US and the West.

"Being part of this Western effort is important," said the ambassador. "It is important for the self-definition of who New Zealand is, I would say."

Dr Daalder said New Zealand should consider not just its relations with the US, but with other allies, particularly Australia.

"God forbid there be a threat directly to New Zealand. Wouldn't it then be good for a country like Holland or Canada or Slovakia or the US to be there [for you]?"

The war in Afghanistan is now almost eight years old and a new push has seen July already become the deadliest month of the war, with 67 international troops killed so far.

Questions about the war are rising in allied countries such as the UK, which has lost 20 soldiers this month.

A review of NZ's Afghanistan commitments is almost finished and will be considered by the Government before a final decision on the SAS or other contributions, such as civilian assistance, is made next month.

Told of Dr Daalder's comments, Mr Key issued a statement last night saying any further commitment would be made in New Zealand's "best interest".