Australian coal exports to China are still facing delays, with protectionism and environmental checks blamed for the slowdown.
Coal export unloading times have almost doubled to 40 days in recent months, prompting Australia to seek an explanation for the delays.
Trade Minister Simon Birmingham said on Friday the government was closely monitoring the situation, but accepted assurances from Chinese authorities the blowout in wait times was not country-specific.
He said domestic protectionist pressure stemming from China's support for its own coal industry and limiting steel production was a factor.
A higher level of quarantine checks for environmental reasons has also impacted Australian exports.
"If that's the case we have nothing to fear because Australia's coal is amongst the best in the world in terms of the environmental standards that come when it is used," Senator Birmingham told ABC Radio National.
"We're trying to understand all of those different moving parts and watching very closely what's happening at each of the ports in terms of the speed of processing times."
Last month, Prime Minister Scott Morrison warned against linking processing delays of coal exports to China with diplomatic tensions.
