U.S. Sens. Elizabeth Warren and Edward Markey are backing legislation that would hike the nation's smoking age by banning the sale of tobacco products to anyone under 21.

Warren said restricting tobacco sales to adults 21 or older will save lives and promote healthier communities.

Warren said in Massachusetts, over 70 cities and towns — more than any other state — have already increased the smoking age to 21.

Fellow Democrat Markey called smoking a public health catastrophe caused by the tobacco industry that intentionally misled the public about smoking risks.

Supporters of the bill said that in the last 50 years, nearly 21 million people in the United States have died from tobacco-related illnesses, making it the leading cause of preventable death in the country.