US pharmaceutical firm Moderna said Thursday it expects to increase global production of its cutting-edge Covid vaccine to up to three billion doses in 2022.

The company said in a statement that it would make new funding commitments to increase supply at its manufacturing facilities in Europe and the United States.

The investments will double the manufacturing of drug substance at its Swiss partner Lonza and more than double output by Rovi in Spain. Production at Moderna's US facilities would increase by 50 percent.

Reaching the three billion mark will depend on the mix of its mRNA vaccine and potentially lower doses of Moderna's pediatric vaccine and variant booster shots, the company said.

The company also raised its supply forecast for this year to between 800 million and one billion doses.

The announcement comes as the spread of virus variants in countries like India have raised concerns about the world's ability to overcome the pandemic.

-As we follow the rapid spread of SARS-CoV-2 variants of concern, we believe that there will continue to be significant need for our mRNA COVID-19 vaccine and our variant booster candidates into 2022 and 2023- chief executive Stephane Bancel said in the statement.

The messenger mRNA vaccines hack into human cells and effectively turns them into vaccine-making factories.