India envoy to Pakistan Gautam Bambawale was informed about Surjeet Singh's expulsion on Thursday.
The US has said that India and Pakistan need to solve issues among themselves following heightened tensions over the expelling of diplomats.
"We've seen the reports of these decisions. These are sovereign decisions that nation-states make, and these are issues that we're going to leave to India and Pakistan to work out," US State Department spokesman John Kirby said on Thursday during a press briefing.
Hours after Indian Foreign Secretary S Jaishankar summoned Pakistan High Commissioner Abdul Basit in New Delhi on Thursday to protest against Mehmood Akhtar, a visa officer at the Pakistan High Commission, who India accused of spying, Islamabad retaliated with a similar move.
In the evening, Pakistan Foreign Secretary Aizaz Ahmad Chaudhry summoned Indian High Commissioner Gautam Bambawale in Islamabad and declared Indian High Commission official Surjeet Singh as persona non grata and asked that he leave the country by Saturday.
Pakistan denied the espionage charges levelled against Akhtar as "false and unsubstantiated", and alleged that Indian police "manhandled" him.
"These are issues that we believe India and Pakistan need to discuss, need to talk about, need to work out between themselves," Kirby added.