New Delhi, Oct. 9 -- The US administration's effort to block immigrant workers' journey from H-1B visas to US permanent residency may leave Indian IT services companies unscathed, as traffic along this route had already slowed to a trickle.

The US on Thursday suspended issuing crucial certificates to leading Indian IT services companies-including Tata Consultancy Services and Infosys Ltd-which are required for H-1B workers to seek green cards. However, data shows these companies these firms account for less than 2% of the total applications filed.

"I am hereby suspending from the permanent labor certification program, some of the largest IT outsourcing firms in the world, Cognizant, Infosys, Tata, Wipro, HCL, and Capgemini; and also due...