The head of the Asian Development Bank (ADB) on Thursday urged US President-elect Donald Trump to continue with a landmark trans-pacific trade deal, but said the region would press on with key accords regardless of his decision.

The US-led Trans-Pacific Trade Partnership (TPP), promoted by outgoing US President Barack Obama as part of his Asia pivot, liberalises inter-regional trade among 12 countries but Trump has charged it will cost the US jobs and hurt American businesses.

Speaking in Manila, Takehiko Nakao said he hoped Trump would not pull out of the agreement which he described as ready to be implemented.
But he added "if the United States doesn't join, there can be so many approaches".

"There is a strong case for certain regional arrangements," he said.

Nakao cited the ASEAN Economic Community (AEC) as well as the China-endorsed Regional Comprehensive Economic Partnership (RCEP) as regional trade arrangements that could still prosper if the TPP fails.

But the ADB chief stressed: "It is important that the US continues to engage in Asia. It is good for the region as a whole and it should be good for the US."

Nakao defended open trade, saying it had helped Asia grow in recent decades.

"We should look at how the world has become a better place for many people from many countries," he added.

Critics have said a US withdrawal would make the TPP meaningless and amount to Washington abdicating its leadership role in the region.