Australia and Sri Lanka will expand the cooperation between their navies in an attempt to crack down on people smuggling, with the Federal Government to give two patrol boats to Sri Lanka.

Prime Minister Tony Abbott, who is in Sri Lanka for the Commonwealth Heads of Government Meeting (CHOGM), finalised the deal with president Mahinda Rajapakse on Saturday as part of diplomatic talks.

Australia will donate two navy ships to Sri Lanka as part of the agreement, which aims to promote enhanced collaboration on people smuggling.

Yesterday's meeting with Sri Lanka's president came after Mr Abbott downplayed concerns the Sri Lankan government may have engaged in war crimes at the end of the country's ethnic war, and talked up the country's economic potential.

That was in contrast to British prime minister David Cameron, who said he was determined to shine an international spotlight on Sri Lanka's human rights issues during CHOGM.

Greens critical of gift, Labor welcomes further cooperation

The Greens have criticised the new deal with Sri Lanka, with party leader Christine Milne saying Australia should not collaborate with the country because of its human rights record.

"In order to sure up Tony Abbott's cruel and hollow policy to stop the boats he is resorting to collaboration with Sri Lanka and will turn a blind eye to human rights abuses," she said in a statement.

"This has nothing to do with fairness, justice or saving lives.

"Any resources provided to Sri Lanka would be better spent in leading a genuine regional solution that cares for refugees by bringing more of them to Australia and by pushing for global action to investigate alleged war crimes."

Opposition frontbencher Tony Burke says he wants to see details of the agreement.

Sorry, this video has expired Australia, UK split on Sri Lanka human rights issue

"There is a lot of questions about what they've announced," he told the ABC's Insiders program.

"I'm not sure how it works... because you are not dealing with a transit country. You're arguably dealing with - there may be some people who claim to be directly seeking asylum."

But Labor's Senate leader Penny Wong has praised the efforts to build closer ties with Sri Lanka.

"Cooperation with our neighbours, cooperation with Sri Lanka is something Labor has said is a priority for a long time," she told Channel Ten.

"I'm glad that the Government after being so negative about, for example, the arrangement with Malaysia, has now come to the view that regional arrangements are important."

Meanwhile, a Sydney-based refugee action group was highly critical of the deal with Sri Lanka.

Refugee Action Coalition spokesman Ian Rintoul says it sends a damaging message to the international community.

"It sends a very strong message that Australia is going to be understanding of the ongoing human rights abuses in Sri Lanka," he said.

"Regardless of what takes place in Sri Lanka, regardless of the level of human rights abuses, there's going to be an international friend in Tony Abbott."

The deal also comes days after reports said a senior Sri Lankan navy officer was arrested for allegedly being involved in people smuggling.

Fairfax media reported the arrest of Lieutenant Commander Sanjeewa Annatugoda, who was once an adviser to Australia on how to stop human trafficking.

Sri Lanka rejects calls for international inquiry

Mr Cameron has said he would push for an international investigation through the UN human rights council unless the Sri Lankan government acts by March to credibly address claims of abuses at the end of the war.

The Rajapakse regime is carrying out its own more limited investigation, but has consistently denied any civilians were killed in the last stages of the war when government troops routed Tamil Tiger rebels in their last stronghold.

However, the UN and rights groups have said as many as 40,000 civilians may have been killed in the onslaught.

Mr Rajapakse responded to Mr Cameron by insisting Sri Lanka should be trusted to conduct its own inquiries and warned against international pressure on his regime's human rights record.

"People in glass houses must not throw stones," Mr Rajapakse said at a press conference in Colombo.

The British prime minister infuriated the government on Friday by travelling to the war-torn Jaffna region, only hours after a Commonwealth summit began in the capital.

It was the first time a foreign leader visited Jaffna since the former British colony gained independence in 1948.

Mr Cameron agrees that talking about the country's development is important, but he says human rights issues should not be overlooked.

"It's important that we talk up the potential of this country. I'm very keen to do that. I think there's immense potential here in Sri Lanka," he said.

"But I think we do that not by gliding over the difficult issues. I think it's right to confront and discuss the difficult issues - the human rights issues, journalistic freedom issues."

'Some of the things he said were aimed at his constituency'

A top Sri Lanka minister has also rejected pressure for an international probe, saying the government would "definitely" not allow one.

"Why should we have an international inquiry? We will object to it... Definitely, we are not going to allow it," said Basil Rajapakse, Sri Lanka's economic development minister and brother to the president.

"It is not new, it is not the first time they are saying it," he said of the pressure for an international inquiry.

Asked about the March deadline for the Sri Lankans to complete their own inquiry, the minister rejected any talk of a timetable being imposed from outside.

"They can't give dates. It is not fair. Even Cameron has said we need time. Even in Northern Ireland it took a lot of time," Basil Rajapakse said.

"We understand some of the things he said were aimed at his home constituency. He was addressing the journalists who travelled with him."

The prime ministers of Canada, India and Mauritius all stayed away from Colombo over Sri Lanka's human rights record.

ABC/wires