The New Zealand analysis finds the agreement with Australia, Brunei, Canada, Chile, Japan, Malaysia, Mexico, Peru, Singapore and Vietnam will boost its gross domestic product by between 0.3 per cent and 1 per cent . Had it pulled out of the agreement leaving the other 10 countries to sign, it would lose $NZ183 million as the other members shut it out of supply chains in order to trade with each other.

The agreement was to have included the United States, which withdrew after President Donald Trump refused to put it forward for ratification. The Canadian analysis finds that Canada does better out of it without the US. Had the United States been included, the agreement would have added $CA3.4 billion to Canada’s economy. Without the US, it will face less competition for trade within the group and get a boost of $CA4.2 billion.

The deal will cut tariffs on trade within a bloc that accounts for 13 per cent of global GDP. Had the US been included the bloc would have accounted for 40 per cent of global GDP.

More than 20 provisions originally included at the insistence of the United State have been suspended or changed in the final text, including rules around pharmaceuticals and intellectual property.

Still in the agreement are investor-state dispute settlement procedures that allow private companies to sue member governments in extrajudicial tribunals. A minor amendment inserted at the request of New Zealand prevents companies that are parties to contracts with governments from suing those governments.