A Syrian human rights activist who fled the country after he was forcibly detained because of his work says the Australian government isn't moving quickly enough on its promise to resettle 12,000 refugees.

It's been six months since the federal government promised to welcome 12,000 refugees from Syria and Iraq, but only 26 have arrived in Australia, Amnesty International say.

Syrian activist Bassam al-Ahmad has partnered with the advocacy group to try and spur the Commonwealth into action, meeting with government representatives and Australian non-government organisations.

"I came here ... to advocate for refugees," the 32-year-old told AAP on the eve of his departure from Melbourne on Sunday.

"I'm here to tell people what's going on in Syria and talk about how they can help the people there."

Mr al-Ahmad had just begun documenting human rights abuses for an independent not-for-profit organisation in Damascus when he was arrested in 2012.

He was detained for 87 days and ordered to stand trial, prompting him to flee across the border into Turkey.

Since the war began five years ago, it has claimed the lives of at least 250,000 Syrians and left more than 11 million displaced.

Amnesty International say the federal government should play a bigger role in Syria's humanitarian crisis beyond its military contributions, which are the second largest behind the United States.

Mr al-Ahmad is worried about how long it is taking Australia to act on then prime minister Tony Abbott's promise to welcome 12,000 refugees.

"We've had good reactions from Australia," he said.

"But what they're doing as a government is not enough."

The longer it takes, the more likely vulnerable refugees will die in the harsh conditions of refugee camps, he says.

"A lot of people died due to the cold in January, and I think the government knows exactly what the situation is and the difficulties there," Mr al-Ahmad said.

The activist also hopes Australia will welcome more refugees beyond its one-off offer.

The Syrian refugee says his time in Australia has shown him how welcoming the community is towards people from different cultures.

"When I was in Sydney I discovered how the community is diverse, but are living together," Mr al-Ahmad said.