(Reuters) -India's Tata Motors and the country's auto parts makers that supply Tesla, among others, dropped on Thursday after U.S. President Donald Trump announced plans for 25% tariffs on all imported cars and auto parts.

Tata Motors slid 5%, while Tesla's biggest Indian supplier, Sona Comstar, dropped over 4%, leading to a 1.2% drop in the auto sector in the world's third-largest auto market.

The 25% tariffs on cars and light trucks imported into the U.S. will start on April 2, while tariffs on auto parts will take effect from May 3. The news rocked the auto sector globally, with Tesla CEO Elon Musk saying the impact on the EV maker is "significant."

The U.S. is a top destination for Tata Motors-owned Jaguar Land Rover's (JLR) luxury cars, which are imported from plants in the UK and Slovakia.

Among other stocks, Samvardhana Motherson, India's biggest auto parts supplier, fell over 2%, while Bharat Forge, which also supplies Tesla, was down 0.4%.

The U.S., Samvardhana's top market along with India, accounts for 20% of its total revenue. North America, led by the U.S., forms a steeper 40% of Sona Comstar's revenue.

The day's decline also mirrors share moves of larger global carmakers, from Toyota and Hyundai, to Stellantis and Ford, all of which fell after Trump's announcement.

(Reporting by Nandan Mandayam in Bengaluru; Editing by Savio D'Souza)