New Delhi, Jul 6 (IANS): Amid reports of Chinese troops' withdrawal from the Galwan Valley in eastern Ladakh, former Union minister and Congress leader Anand Sharma termed it as a "positive" development and insisted that there is a need for "eternal vigil".

"Disengagement and de-escalation on LAC is a priority. India must insist for pull back at Pangong Tso. There is need for eternal vigil," said Sharma.

The head of foreign affairs department of the Congress also said that China needs to "realise that stability" and peace at the borders and restoration of status quo ante is a must to "rebuild trust."

The Congress which has been critical of Prime Minister Narendra Modi over his handling of the Chinese transgressions at LAC and has accused him of misleading the nation, gave credit to the Indian Army for the Chinese pull back.

"Proud of our Army for standing firm in nation's defence," said Sharma.

Indian and Chinese troops have retreated two kilometres each along the Line of Actual Control (LAC) in the Galwan Valley, where 20 Indian and an unknown number of Chinese soldiers were killed in a violent face-off last month.

Top official sources told IANS that both sides retreated two kilometres simultaneously on Sunday, following several rounds of talks which had begun after the clash on June 15.

The disengagement between Indian and the People's Liberation Army (PLA) troops happened as per the agreed terms in the corps commanders' meeting.

With the retreat from both sides, a four kilometre no-man zone has been created. "Four kilometres in the highly mountainous terrain like Galwan valley, deprives both sides to see each other's installations and reinforcements," sources said.

The two sides have also agreed, sources said, not to do any aerial surveillance of the retreated area, to rebuild trust which was badly damaged due to the June 15 clash.