Ukraine has become the latest country to ratify the climate deal agreed in Paris last year.
That takes the total number of countries that have formally ratified the agreement to 29. They account for 40% of global greenhouse gas emissions.
Bahamas, Norway and Belgium are among the countries which have also ratified the climate deal which means they will take action to limit the temperature rise to below 2°C.
The agreement was signed by more than 170 countries, including the UK, in April.