Logos of Tata Consultancy Services (TCS) are displayed at the venue of the annual general meeting of the software services provider in Mumbai, June 29, 2012.Reuters

India's largest IT services exporter Tata Consultancy Services Ltd (TCS) is facing legal trial in the US over allegations of discrimination against American workers, Bloomberg reported.

A federal judge in Oakland, rejected the IT major's plea to dismiss the lawsuit filed in 2015, accusing the company of violating anti-discrimination laws by favouring South Asians.

Further the judge has also expanded the case into a class action on behalf of American workers who lost their jobs at TCS offices in the US because they were not assigned any project, reported the agency.

Another Indian IT firm and TCS rival is also facing a similar lawsuit in Milwaukee. Both the IT firms came under pressure from Trump administration to hire more American locals.

Following this, earlier in May, Infosys announced plans to hire 10,000 US workers over the next two years and open four technology centres in the US, starting with Indiana.

The lawsuit against TCS was filed by an IT worker named Brian Buchanan, who claimed he was subjected to "substantial anti-American sentiment" within the company and was ultimately terminated within 20 months despite having almost 20 years of experience in the field, according the report.

Buchanan further claimed that he was among 400 people terminated, but said he was asked to stay on for a few months to train the Indian TCS employees who were replacing him.

However, TCS argued that Buchanan's experience does not prove he was a victim of bias. He has "no idea" whether the application process was discriminatory because he did not attend any of the town hall meetings he was invited to during the Edison transition to learn about open positions with TCS and how to apply for them—and he did not apply for a specific job, the company said in a court filing.