The Commonwealth Secretary-General opened talks with Sri Lanka on Sunday by pushing for judicial independence on the island, as Canada renewed calls to boycott the bloc's summit in Colombo later this year.

Secretary-General Kamalesh Sharma is holding talks with Sri Lankan leaders in Colombo on the rule of law and the separation of powers after the island defied international appeals and sacked its chief justice in January, the bloc said.

Commonwealth Secretary-General, Kamalesh Sharma, opened talks with Sri Lanka on Sunday by pushing for judicial independence on the island. (Credit: ABC)

Mr Sharma's four-day visit to Sri Lanka came as Ottawa urged others in the 54-member grouping to stay away from the November Commonwealth Heads of Government Meeting (CHOGM) hosted by Colombo.

Canada had reported Sri Lanka to the Commonwealth over the alleged violation of the organisation's democratic values by ignoring two court rulings and sacking Chief Justice Shirani Bandaranayake last month.

She had given rulings which were thought unfavourable to President Mahinda Rajapakse's regime which is also accused of failing to probe war crimes allegations against Sri Lankan troops which defeated Tamil rebels in 2009.

"Sharma is expected to discuss, among other issues, options for advancing Commonwealth values and principles, including the independence of the judiciary and the separation of powers," the Commonwealth said in a statement.

The statement said the Secretary-General was also discussing arrangements for the November summit which is going ahead despite Canadian objections.

Canadian Prime Minister Stephen Harper has warned that he may refuse to attend the summit unless Sri Lanka addresses allegations of atrocities during the closing battles of the war against separatist Tamil rebels in 2009.

Mr Sharma in September asked the two countries to resolve their differences and ensure the smooth conduct of the summit.

Sri Lanka has denied allegations from international rights groups that government troops killed up to 40,000 civilians during the civil war. AFP