The US Treasury Department has said it supports a global minimum corporate tax rate of at least 15 per cent — below the minimum 21 per cent it has been seeking to impose on the foreign profits of US-based companies.

The offer comes as the Organisation for Economic Cooperation and Development and the Group of 20 major economies seek an agreement on a minimum corporate tax rate.

It is part of an effort to end what the Treasury calls “a race to the bottom” as countries compete with each other to cut corporate tax rates and lure multinational companies.

The OECD estimates that governments lose up to $240 billion a year to companies that shift earnings among countries to lower their tax bills.

Competition to cut corporate tax rates has been “undermining the United States’ and other countries’ ability to raise the revenue needed to make critical investments,” the Treasury said in a statement, adding that its proposal had been received positively by other countries. Treasury emphasised that the proposed 15 per cent is a floor and said that “discussions should continue to be ambitious and push that rate higher”.