The Indian military on Monday accused China of staging "provocative" action on their contested Himalayan border where 20 Indian troops were killed in a battle in June.
The incident happened in the eastern Ladakh region on Saturday night, according to an Indian defence ministry statement which gave few details of the events.
Three Indian military sources told AFP however that China's People's Liberation Army crossed into a zone that India considers its territory and were pushed back without violence.
Military commanders from the two sides held talks on Monday in a new bid to ease tensions between the nuclear-armed neighbours who fought a border war in 1962 and have staged regular high altitude clashes since.
China did not confirm the incident, but the foreign ministry said its troops have "always strictly respected" the unofficial border known as the Line of Actual Control.
On June 15, troops from the two sides fought hand-to-hand combat in Ladakh in which 20 Indian troops were killed. China acknowledged casualties but did not give figures.
The two sides blame each other for recent clashes and the two armies have since poured tens of thousands of troops into the region. Military and diplomatic talks are at an apparent stalemate.
The latest showdown was at Pangong Tso, a lake at 4,200 metres altitude, that is one of several hotspots where troops have massed since June.
The PLA "carried out provocative military movements to change the status quo" at the border, according to India's defence ministry.
"Indian troops pre-empted this PLA activity on the southern bank of Pangong Tso lake, undertook measures to strengthen our positions and thwart Chinese intentions to unilaterally change facts on ground," said the ministry.
Senior officers met at a border post near the scene of the standoff on Monday, it added.
According to Indian military sources, speaking on condition of anonymity, Indian troops pushed back Chinese troops who crossed the Line of Control.
"PLA soldiers walked into our area near the south bank of Pangong, but our soldiers were prepared and quickly pushed them back without any violence," said one source.
"They tried to come in again several hours later but we stood firm. There has been no such confrontation in this area in the past."
China's foreign ministry said Chinese troops "have always strictly respected the Line of Actual Control and never crossed the line."
"Border troops from both sides have maintained communication over issues on the ground," foreign ministry spokesman Zhao Lijian told a press briefing.
Amidst calls for boycotts of Chinese goods, India has stepped up economic pressure on China since the June battle and repeatedly warned that relations would suffer unless its troops pull back.
India has banned at least 49 Chinese owned-apps, including the Tik Tok video platform, frozen Chinese firms out of contracts and held up Chinese goods at customs posts. China has complained about the action and warned that Indian consumers will suffer.
"We have very large number of Chinese forces (at the border) and frankly we are at a loss to know why," Foreign Minister S. Jaishankar said in an interview with the Hindustan Times released Sunday.
"There will naturally be issues if the peace and tranquility is put under stress," he added.
