Australian Foreign Minister Bob Carr Monday headed to Libya to press for the release of an International Criminal Court (ICC) team who are being held after meeting the son of dead dictator Muammar Gaddafi.

The delegation, including Australian Melinda Taylor and colleagues from Lebanon, Russia and Spain, were detained June 7 as they helped Seif al-Islam choose a defence lawyer. Global pressure has been building on Tripoli ever since over the arrests.

Taylor and Lebanese-born interpreter Helene Assaf were detained in the town of Zintan and are accused of smuggling documents to Seif al-Islam. Two male colleagues travelling with the ICC delegation have also remained with Taylor and Assaf.

Consular access

"It is Australia's view that Ms Taylor should be afforded consular access, and should no longer be detained," Carr said on Monday, ahead of a visit to Libya for meetings with authorities.

The ICC in The Hague, U.N. Security Council, the head of NATO and rights groups have all called for Libya to release the ICC delegates in what is shaping as the country's biggest diplomatic challenge since last year's uprising which ended Gaddafi's 42-year rule.

Libyan prosecutors said they want to detain Taylor and Assaf for 45 days while they are investigated for allegedly passing documents to Saif al-Islam from his fugitive right-hand man Mohammed Ismail.

Australia has said the women should have been afforded the diplomatic protection while in Libya because they were doing work for the ICC.

Limited hope

Carr raised the issue directly with Libyan Foreign Minister Ashour bin Hayal on the sidelines of non-proliferation talks in Istanbul on Sunday, but said he had only "modest" expectations that the two women will be released.

"But we will press the case that Ms Taylor is in Libya under the mandate of the ICC and United Nations Security Council, and this mandate provides a legal immunity," Carr said in a statement.