By Karen Middleton in Colombo

Two conservative prime ministers, two very different approaches.

British Prime Minister David Cameron has contradicted his Australian counterpart, Tony Abbott's approach on human rights in Sri Lanka.

Yesterday, Mr Cameron became the first foreign leader since 1948 to visit the Tamil lands in Sri Lanka's north, while attending the Commonwealth Heads of Government Meeting.

He's sounded a warning to Sri Lanka over its current internal investigation into allegations of war crimes.

"Let me be very clear," Mr Cameron said. "If that investigation is not completed by March then I will use our position on the UN human rights council to work with the UN Human Riights commission and call for a full, credible and independent international inquiry."

Mr Abbott is also here but has opted for a softer approach.

He told the CHOGM opening ceremony yesterday that leaders had come to Sri Lanka "to praise as much as to judge" the host nation.

Earlier, at a news conference, Mr Abbott said the Australian Government deplored any use of torture.

"But we accept that sometimes in difficult circumstances, difficult things happen. The important thing is to act as quickly as you can to bind up the nation's wounds."

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