Labor insists the inquiry will happen, but wants more time to consider the terms of reference.

Labor's Kimberley Kitching and Senator Patrick were to jointly sponsor a referral on Thursday morning for a wide-ranging inquiry on Australia's relations with China, but the move was abruptly withdrawn by Labor on Wednesday evening. It is now postponed till the Senate sits in September.

The inquiry envisaged hearing from the government agencies, businesses working in China, people claiming human rights abuses, academics, state and territory governments and possibly also the United States. The Chinese ambassador would be invited to appear, and the Chinese government to make a submission.

The inquiry was to canvass a suite of contentious and diplomatically sensitive topics, including the management of diplomatic and consular arrangements, and "Australian and Chinese perspectives on ... regional and global security issues".

It was also to look at "tourism, cultural exchanges and people-to-people ties", dialogue on human rights issues and education and research links.

Chinese students are by big far the biggest cohort of international students, making up 30 per cent of Australia's 620,000 international students this year, with the proportion rising. About 40 per cent of the 26,600 students at the Australian National University are international students. The university was recently caught up a hacking scandal in which China has been implicated by the intelligence community. Almost 20 years of personal data from students and staff was accessed in the hack.

The Senate inquiry would have looked at trade, investment and infrastructure, including the belt and road initiative, which has caused alarm as the extent of China's inroads into Pacific Island nations has been belatedly recognised, and after the Victorian government become the first in Australia to sign a belt and road memorandum of understanding with China last year.

Delving into a minefield of agreements and relationships with China, the inquiry was to have considered relationships that state and local governments, universities and other academic bodies, businesses and non-government organisations have with China.

In another sweeping remit, the inquiry was to consider "the management of a mutually respectful and beneficial bilateral relationship".

The inquiry proposal comes amid tensions between China and the US over trade at China's build-up of infrastructure in the South China Sea, and as US president Donald Trump pursues an unpredictable and unorthodox foreign policy, forcing Australia to rethink its position in the region.

Senator Kitching, who chairs the Foreign Affairs, Defence and Trade References Committee which would conduct the inquiry, said it would go ahead but had simply been postponed to ensure the terms of reference had bipartisan support, with "a variety of people" wanting to consider it.

"People just wanted to think about some of the terms of reference," she said. "It's not withdrawn. It will be happening. It's just that it's been postponed to the next sitting day."

Senator Patrick said a "wide-ranging and rigorous inquiry" was in the national interest. Australia's relationship with China was extremely important and Australia must maximise benefit from the relationship, but also understand where to be cautious.

"It is regretful that Labor decided at the last minute to withdraw from sponsoring the motion," he said, hoping the party would "find a way" to support it in September.

Last year, Senator Patrick tried to set up an inquiry into Victoria's decision to sign a belt and road agreement with China. The move was stymied by Labor and Liberal, despite Prime Minister Scott Morrison criticising the Victorian government for not consulting the federal government.

Senator Patrick said he was "getting the feeling the parliament is starting to self-censor itself on what is one of Australia's most important bilateral relationships".

"That is not a healthy state of affairs for our democracy, and doesn't help efforts to think calmly and clearly about how this key relationship is to be managed in the future."