WASHINGTON - US President Barack Obama has pledged more than $4.2 billion in funding to expand computer science education in the country's schools.

"In the new economy, computer science isn't an optional skill -- it's a basic skill, right along with the three 'Rs (reading, writing and arithmetic)," Obama said in his weekly radio address at the weekend.

Obama emphasized that nine out of 10 parents surveyed last year in the United States want computer science taught at their children's schools.

He also cited estimates that just one quarter of all the K-12 schools in the country offer computer science classes and that 22 of the 50 US states still don't allow computer science courses to count toward a diploma.

"So I've got a plan to help make sure all our kids get an opportunity to learn computer science, especially girls and minorities. It's called Computer Science For All," Obama said.

"And it means just what it says -- giving every student in America an early start at learning the skills they'll need to get ahead in the new economy."

Under the plan, the US Department of Education will provide four billion dollars in funding over the next three years to states that propose comprehensive five-year "Computer Science for All" plans.

In addition to state-level grants, the budget plan will dedicate 100 million dollars in competitive grants directly for schools to execute computer science expansion efforts for all students, including traditionally underrepresented students, and serve as models for national replication.

The US government will also leverage existing resources, including 135 million dollars from the National Science Foundation and the Corporation for National and Community Service, to train more computer science teachers for the initiative.

In 2014, Obama became the first US president to write a line of code, and issued a broad call to action to expand computer science across the nation's classrooms. He also mentioned his computer science push in his last State of the Union earlier this month.