Congress leader Rahul Gandhi on Saturday launched a scathing attack on Prime Minister Narendra Modi over the Sino-India border standoff, charging him with being 'scared' of the eastern neighbour.

Before the stand-off at eastern Ladakh, where the disengagement process has been completed with the withdrawal of troops, weapons and other military hardware from the North and South banks of Pangong lake areas, the Chinese "tested the idea in Dokhlam (in 2017)," he said.

"Essentially the Chinese occupied certain strategic areas in our country. They first tested the idea in Dokhlam.

They tested the idea to see how would India react and they noticed India did not react. And then they carried out the idea again in Ladakh and also I believe in Arunachal Pradesh," he said.

Launching his three-day tour of Tamil Nadu ahead of the April 6 Assembly polls, the Congress leader, while interacting with advocates here, reiterated his "hum do hamare do" jibe at the ruling dispensation at the Centre.

Speaking in detail over the border standoff, Gandhi said Modi's first reaction to the Chinese incursions was "that nobody has come into India."

"That indicated to the Chinese that the Prime Minister of India is scared of them. That is the message he indicated to the Chinese, that he is scared of them and the Chinese understood it.

And since then the Chinese have negotiated on that principle," he said.

"They know that the Prime Minister of India cannot stand up to them. Mark my words, our land in Depsang, which is the most important land, is not going to come back to under this government.

The Prime Minister will not get that land back. He will pretend everything is sorted out, but India is going to lose that territory," he charged.

Giving such a message to the Chinese was "very dangerous to the future because the Chinese are not going to stop with Ladakh," he alleged.

He said the government under the Congress "always dealt with the Chinese without any hesitation."

"The Chinese understood very well that India cannot be pushed around. Even in 2013 when the Chinese entered into India, we took action that forced them, forced them to compromise...we went and occupied other spaces," he said.

"They have now understood the Prime Minister doesn't have the courage...the Chinese know the Prime Minister is going to compromise," he added.