NIAGARA FALLS, Ontario (AP) – The United States and Canada say they will update a key agreement to protect the Great Lakes.

Environmental groups have pushed the leaders of both countries to rewrite the 1972 Great Lakes Water Quality Agreement in response to new threats to the world’s biggest surface freshwater system.

Secretary of State Hillary Rodham Clinton and Canadian Foreign Affairs Minister Lawrence Cannon said Saturday that the agreement will be revised to address such issues as invasive species, chemicals and climate change. The agreement was last updated in 1987.

The officials made the announcement during a ceremony marking the 100th anniversary of the Boundary Waters Treaty of 1909. The treaty created an international commission to settle disputes between the two countries.