China's President Xi Jinping committed to greater Antarctic cooperation with Australia Tuesday, while fulfilling a long-held dream to visit the nation's smallest state in a trip which included a close encounter with a Tasmanian devil.

Xi supported the use of Australia and particularly of Tasmania as a gateway to the frozen continent in an agreement with Prime Minister Tony Abbott in the state capital Hobart, where the flagship of China's Antarctic programme, the Xue Long, is docked.

The memorandum of understanding also reaffirmed China's promise to respect the icy region as a natural reserve that will not be exploited, while committing the two countries to collaborate on scientific projects.

"Antarctica's unique geographical, climatic and ecological conditions have offered an opportunity to gain an understanding of the evolution of Earth," Xi said, speaking through a translator.

The deal to collaborate in the hostile, remote and fragile Antarctic came three decades after China's first expedition to the region, and follows reports last month of plans to build an airfield there to support its four research stations.

About 30 nations operate permanent research stations in Antarctica including the US, Russia, Australia, Britain, France and Argentina. Hobart, which is home to the Australian Antarctic Division, is a key shipping gateway to the area.

The signing capped a whirlwind trip to the so-called Apple Isle by the Chinese leader, who has visited every other Australian state and territory and joked Monday that he should receive a certificate for his travels across the country.

- Moved by students' letter -

Xi said he chose to visit the southern state following the weekend G20 summit in Brisbane after receiving a letter from primary school students in Launceston in the state's north.

"In their letter, they describe Tasmania's unique products and beautiful scenery, they hand-wrote the letter in Chinese," Xi said in his address to the Australian parliament in Canberra Monday.

"And their words have filled me with curiosity."

Andy Muller, principal of Scotch Oakburn College, told AFP his students were thrilled about their meeting with the president and it was "one of the most exciting days of their lives".

"The president invited them to come to China to visit, sightsee and study, and the students are all very motivated to continue with their Chinese and go over there."

Xi and his wife Peng Liyuan were warmly welcomed when they touched down in Hobart and were introduced to three orphaned baby Tasmanian devils, the black, furry native animal named for the state.

Dozens of Xi supporters waving flags and banners also gathered outside the state's government house and at Hobart wharf where the agreement was signed.

Tasmania, which in 1980 became the sister state of Fujian province where Xi previously served as governor, is hoping to cash in on the growing economic clout of China's middle classes through food and wine exports, renewable energy projects and tourism.

The state's Premier Will Hodgman signed four agreements with China in Canberra on Monday which will increase Tasmania's links with the China Development Bank Corporation and with Fujian and Shaanxi provinces as well as supporting the development of a wind farm.

Peter Chung, a third-generation Chinese Australian and retired businessman, said Xi's visit would help to put the state on the map.

"When I travelled overseas, not many people I met knew where Tasmania was," Chung, who was the president of Tasmania's Chinese Community Association for three decades, told AFP.

"But now, people say -- I know where it is."

China is the largest source of international visitors to Tasmania, with a 61 percent increase in the number of tourists to 20,400 in the year to June, Tourism Tasmania data showed.

Xi on Monday signed a historic free-trade agreement with Australia in Canberra.