Both the US and Australian governments were pivotal in bringing about the signing of the Trans-Pacific Partnership (TPP), a trade deal between 12 nations which was signed in February after seven years of negotiations, and Turnbull said while the TPP had been approved in many nations, including Australia, it was still under review in the US, Xinhua news agency reported.
Despite the delay, the prime minister said Obama was confident it would be sorted by the end of the year.
"I've had a good discussion this morning (Thursday) with President Obama on a range of global and regional issues, one of which was the progress of the TPP trade deal," Turnbull said.
"As you know, it is another one of the big trade deals that has been agreed (upon). It has to be ratified by the Congress, but the president is confident it can be ratified before the end of the year. So we're very encouraged by that."
Turnbull said Obama also thanked Australia for its "extraordinary" contribution to the war against Islamic State (IS) in the Middle East, in which Australia has contributed both attack and support aircraft to the coalition effort.
"(Obama) briefed me on developments there from his perspective and I did the same from ours. He thanked Australia for what he described as our extraordinary contribution to the battle against IS," Turnbull said.
The prime minister said the conversation also briefly turned to regional stability, with both leaders agreeing with that any issues in the Asian region must be "resolved peacefully".