Prime minister Narendra Modi should tell the country how the Chinese occupied Indian territory and why 20 soldiers were killed, Congress president Sonia Gandhi said Wednesday.

Her statement comes after 20 Indian Army personnel, including a Colonel, were killed in a violent clash with the Chinese army in the Galwan Valley in eastern Ladakh on Monday night.

"Today when there is so much anger over Chinese intrusion, the prime minister should come out and tell the nation how the Chinese managed to commit this act of aggression," Gandhi said in a video message

The Congress chief also asked how much of Indian territory has been occupied by China and what is the government's strategy to deal with the situation.

"The prime minister should tell the nation how the Chinese occupied Indian territory and why 20 of our brave soldiers were martyred," she asked.

Gandhi said in this time of crisis, the Congress stands with the Indian Army, its soldiers and their families, and the government.

"I'm confident that the entire country will unite to face the enemy in these challenging times," she said.