Breezy Caribbean island tax havens also declined to sign on, including Barbados, Saint Vincent and the Grenadines. Hungary and Estonia, which are keen to preserve their ultra-low tax regimes, joined the dissenters, as did Kenya, Nigeria, Peru and Sri Lanka.
France, which has led the charge for a tax on digital giants in particular, signaled it would work to bring reluctant countries in line. “I will ask them to make all the necessary efforts to join this historic agreement,” Finance Minister Bruno Le Maire said.
O.E.C.D. officials had hoped to seal the framework last year, but their efforts were delayed by the pandemic and by a twist in the Trump administration’s stance as it effectively sought to allow some American companies to choose their tax treatment worldwide. Mr. Biden’s team dropped that insistence.
Ms. Yellen cast the framework as a victory for tax fairness, saying that decades of competition among countries to reduce tax rates to woo corporations “not only failed to attract new businesses, they have also deprived countries of funding for important investments like infrastructure, education and efforts to combat the pandemic.”
In place of that race to reduce rates, she said, “America will enter a competition that we can win; one judged on the skill of our workers and the strength of our infrastructure.”
Conservative economists — including some who served in Mr. Trump’s administration — have praised global efforts to reduce corporate taxes, predicting they would bolster economic growth and worker incomes.
Yet for all the talk of fairness, critics said the plan was hardly watertight.
Alex Cobham, the chief executive of the Tax Justice Network, an advocacy group based in London that fights tax avoidance, said that although a higher effective minimum tax rate would benefit most countries — including the richest — the O.E.C.D. plan “gives little to lower-income countries and leaves much of the incentive for profit shifting intact.”