A new row over free trade will increase pressure on Opposition Leader Bill Shorten to toughen his stance on foreign policy, as Labor’s Left faction pushes for stricter conditions on Australia’s next big trade deals.

The powerful faction has agreed to pursue the new demands at Labor’s national conference in six weeks, sharpening a dispute over a potential deal with China and other Asian nations with $392 billion in annual trade with Australia.

The national Left agreed at a meeting in Melbourne on Saturday to insist on stronger labour safeguards in trade deals to stop the use of prison workers and protect the right to strike – two big issues with China.

Trade will be a hot topic for Opposition Leader Bill Shorten at Labor's national conference in December. Credit:AAP

The debate will set official Labor Party policy and shape decisions by Mr Shorten and his team if he wins the next election.