It follows concerns that tech prices could skyrocket, as many gadgets are made in China, with the US president saying he will give more detail on Monday.

Smartphones, laptop computers, memory chips and other electronics will be exempt from President Trump’s so-called reciprocal tariffs, another step back that could ease some consumer concerns about an immediate jump in costs for tech products imported from China.

The portrait of Mr. Obama, which was unveiled in the East Room during the administration of President Joseph R. Biden Jr., shows the former president in a dark suit and silver tie, standing with his hands in his pockets. The background is white; the portrait was based on photographs taken by the artist Robert McCurdy.