PARIS: A milestone global deal to ensure big companies pay a minimum tax rate of 15% and make it harder for them to avoid taxation has finally been agreed after Ireland, Estonia and Hungary signed up to the elusive accord.

The deal aims to end a four-decade-long "race to the bottom" by governments that have sought to attract investment and jobs by taxing multinational companies only lightly and allowing them to shop around for low tax rates.

Negotiations have been going on for four years, moving online during the pandemic, with support for a deal from U.S. President Joe Biden and the costs of the COVID-19 crisis giving it additional impetus in recent months.

The deal aims to prevent large firms from booking profits in low-tax countries like Ireland regardless of where their clients are, an issue that has become ever more pressing with the rise of "Big Tech" giants that can easily do business across borders.

Minimum tax rate of 15%: Milestone global corporate tax deal finally gets agreement

Out of the 140 countries involved, 136 supported the deal, with Kenya, Nigeria, Pakistan and Sri Lanka abstaining for now.The Paris-based Organisation for Economic Cooperation and Development (OECD), which has been leading the talks, said that the deal would cover 90% of the global economy.

"Today we have taken another important step towards more tax justice," German Finance Minister Olaf Scholz said in a statement emailed to Reuters.

"We now have a clear path to a fairer tax system, where large global players pay their fair share wherever they do business," his British counterpart Rishi Sunak said.

With the ink barely dry on the deal, some countries were already raising concerns about its implementation.

The Swiss finance ministry demanded in a statement that the interests of small economies be taken into account and said that the 2023 implementation date was impossible.