The development comes just days ahead of External Affairs Minister Salman Khurshid's May 9 visit to Beijing.
"Intensive diplomatic contacts led by Foreign Secretary Ranjan Mathai, coordinating with military authorities and Ambassador Jai Shankar in Beijing, which led to flag meeting in which face-to-face situation was resolved," said an official source.
Besides the diplomatic negotiations, the local commanders are believed to have held two rounds of flag meetings over the weekend, besides the three inconclusive flag meetings held earlier.
Khurshid, who had earlier said he intended to go to Beijing, had over the past few days hinted he could reconsider his Beijing trip if there is no progress in resolving the border stand-off.
"I can't say we have satisfaction (from Beijing) at this stage," Khurshid has said.
Khurshid said a review of his visit has not been done "as of now" but "what will happen tomorrow, one can't predict today".
He is travelling to Beijing to prepare for the visit of Chinese Premier Li Keqiang in the third week of May.
Chinese troops had entered 19 km on the Indian side of the LAC -- the de-facto border -- and pitched tents, causing concern in India. Indian troops also moved troops closer to the area.
After prolonged negotiations, Indian and Chinese soldiers Sunday evening at around 1930 hours pulled back to their positions that existed prior to April 15, the sources said.
In Beiing, Chinese Foreign Ministry Spokesperson Hua Chunying told a media briefing Saturday that both nations are committed to resolving the border dispute through talks without letting it to "affect" bilateral ties.
The Chinese were insisting that India dismantle infrastructure it has built in eastern Ladakh, including bunkers and roads close to LAC.
Last week, Indian Army Chief General Bikram Singh had informed the Cabinet Committee on Security of the situation on the LAC.
The opposition Bharatiya Janata Party (BJP) has criticised the scheduled May 9 visit of Khurshid unless the Chinese troops withdraw.