Sweeping changes to the global tax system were agreed to yesterday by more than 130 countries that could wreak havoc on Bermuda’s major economic pillar – international business.

The changes to how global companies are taxed, includes a 15 per cent minimum corporate tax rate, aimed, in part, at deterring companies from using a network of financial services jurisdictions to legally reduce their corporate tax bills.

While it was believed that some carve-out would be arranged to protect the international insurance and reinsurance industries that are the financial backstop in the event of major catastrophes, no such arrangement has yet been made.

The pact finalised today, will be taken on Wednesday to the G20 Finance Ministers meeting in Washington DC.

It will then go to the G20 Leaders Summit in Rome at the end of the month, according to an Associated Press report.

The deal, led by the Paris-based Organisation of Economic Co-operation and Development, is designed to deter multinationals from stashing profits in low-tax countries.

The OECD said it was an attempt to address how globalisation and digitalisation had changed the world economy.

It would allow countries to tax some of the earnings of companies located elsewhere that make money through online retailing, web advertising and other activities.

US President Joe Biden has been one of the driving forces behind the agreement as governments around the world seek to boost revenue following the COVID-19 pandemic.

The agreement among 136 countries representing 90 per cent of the global economy, was announced after the OECD-hosted talks that led to it. The organisation said the minimum tax would reap $150 billion for governments.

“Today’s agreement represents a once-in-a-generation accomplishment for economic diplomacy,” US Treasury Secretary Janet Yellen said in a statement.

She said it would end a “race to the bottom” in which countries outbid each other with lower tax rates.

“Rather than competing on our ability to offer low corporate rates,” she said, “America will now compete on the skills of our workers and our capacity to innovate, which is a race we can win.”

The deal faces several hurdles before it can take effect.

US approval of related tax legislation proposed by Biden will be key, especially since the US is home to many of the biggest multinational companies. A rejection by Congress would cast uncertainty over the entire project.

The big US tech companies such as Google and Amazon have supported the OECD negotiations. One reason is that countries would agree to withdraw individual digital services taxes they have imposed on them in return for the right to tax a part of their earnings under the global scheme.

That means the companies would deal with just one international tax regime, not a multitude of different ones depending on the country.

“This accord opens the way to a true tax revolution for the 21st century,” said French finance minister Bruno Le Maire.

"Finally the digital giants will pay their just share in taxes in the countries – including France – where they produce.”

Yesterday, Ireland announced that it would join the agreement, ditching a low-tax policy that has led companies like Google and Facebook to base their European operations there.

Although the Irish agreement was a step forward for the deal, developing countries have raised objections and Nigeria, Kenya, Pakistan and Sri Lanka have indicated they will not sign up.

Anti-poverty and tax fairness advocates have said the bulk of new revenue would go to wealthier countries and offer less to developing countries that are more dependent on corporate taxes.

The G-24 group of developing countries said that without a bigger share of revenue from reallocated profits, the deal would be “suboptimal” and “not sustainable even in the short run”.

Countries would sign up to a diplomatic agreement to implement the tax on companies that have no physical presence in a country but earn profits there, such as through digital services. That provision would affect around 100 global firms.

The second part of the deal, the global minimum of at least 15 per cent, would apply to companies with more than 750 billion euros ($864 billion) in revenue and be passed into domestic law by countries according to model rules developed at the OECD.

A top-up provision would mean tax avoided overseas would have to be paid at home. So long as at least the major headquarters countries implement the minimum tax, the deal would have most of its desired effect.