PORT MORESBY (REUTERS) - Malaysian Prime Minister Mahathir Mohamad said nations needed to re-evaluate globalisation and economic integration because it was leaving some people behind and fuelling inequality.

Speaking at the Asia-Pacific Economic Cooperation (Apec) summit in Papua New Guinea on Saturday (Nov 17), Dr Mahathir called for a more level playing field on trade between rich nations and the developing world.

"The benefits of free and fair trade and economic integration have been ruptured, exemplified by Brexit and trade wars between major economies," Dr Mahathir said.

"The trade war between the US and China has amplified further the disruption to our trade and commerce."

Australian Prime Minister Scott Morrison, however, used his Apec speech to give a full-throated defence of free trade.

"I know there are legitimate questions around trade arrangements," said Mr Morrison. "But the solution to perceived unfair trade practices is more likely to be found around the negotiating table than it is in re-building a tariff wall."

"Our efforts must be about persuading and convincing our peoples again about the domestic benefits (of free trade)."

The speech was a clear reference to the escalating trade war between the United States and China, along with the general protectionism of US President Donald Trump.

"We are witnessing a rising tide of trade protectionism along with financial volatility in some emerging economies,"said Mr Morrison.

"The test for us now is to stand up for the economic values we believe in and show how they work."

Mr Trump has skipped the annual meeting of the 21-nation grouping, but US Vice-President Mike Pence will be speaking later on Saturday.

Mr Pence tweeted he would discuss "Trump's commitment to prosperity, security and freedom in the Indo-Pacific".

Chinese President Xi Jinping will also be speaking at the summit and is expected to emphasise the importance of free trade and globalisation and warn against protectionism.

China has also been at loggerheads with the United States over its territorial ambitions in the Pacific, encapsulated by Mr Xi's Belt and Road Initiative.

Unveiled in 2013, the Belt and Road initiative aims to bolster a sprawling network of land and sea links with South-east Asia, Central Asia, the Middle East, Europe and Africa.

China's efforts to win friends in the resource-rich Pacific have been watched warily by the traditionally influential powers in the region - Australia, New Zealand and the United States.