Smartphone sales are expected to fall by 5 percent across the world compared to previous estimates, as the novel coronavirus pandemic disturbs supply chains and curbs demands, said Roger Sheng, vice-president of research at global consultancy Gartner Inc.

Out of that, 5G smartphone production is projected to drop by more than 10 percent, or about 30 million units.

"The virus has left a larger stockpile of 4G smartphones than expected. This would delay people's purchase of 5G phones," Sheng said. "But in the long term, it will also propel smartphone makers to accelerate the transition from 4G to 5G phones."

Meanwhile, the consultancy forecast a cut of $10.8 billion in semiconductor revenue for 2020, with slight rebounds expected in the second half of the year. The contagion has hurt mostly the demand side, such as reduced needs for consumer electronic goods and automobiles.

Gartner also tuned down growth forecast for chips from 12.5 percent to 9.9 percent, with revenue set to fall below $460 billion.