Photo/Illutration In this Sept. 2018 photo Border Roads Organization workers rest near Pangong Lake in the Ladakh region of India. (AP Photo)

BEIJING-- China said Indian forces crossed into territory it holds along their disputed border and fired warning shots at a Chinese patrol in a move it called a “serious military provocation” and a violation of their agreements.

The nuclear-armed rivals have been engaged in a tense standoff in the cold-desert Ladakh region since May, and their defense ministers met Friday in Moscow in the first high-level direct contact between the sides since the standoff began.

China’s western military command said the incursion occurred Monday along the southern coast of Pangong Lake in the area known in Chinese as Shenpaoshan.

After shots were fired, Chinese forces took “necessary measures to stabilize and control the situation,” the command said, in the statement citing spokesman Zhang Shuili. It demanded the Indian forces withdraw and investigate the move to open fire.

There was no word of casualties on either side.

Late last month, India says its soldiers thwarted the Chinese military’s moves “to change the status quo” in violation of a consensus reached in past efforts to settle the standoff.

The activity last month and on Monday were alleged to have occurred on the southern bank of Pangong Lake, a glacial lake divided by the de facto frontier and where the India-China faceoff began in early May.

The standoff escalated to a medieval, nighttime clash June 15 that was the deadliest conflict in 45 years between the nuclear-armed rivals. According to Indian officials, Chinese troops atop a ridge at the mouth of the narrow Galwan Valley threw stones, punched and pushed Indian soldiers down the ridge at around 4,500 meters. India said 20 of its soldiers were killed, including a colonel. China did not report any casualties.

The disputed and undemarcated 3,500-kilometer border between India and China, referred to as the Line of Actual Control, stretches from the Ladakh region in the north to the Indian state of Sikkim. The nuclear-armed Asia giants fought a border war in 1962 that also spilled into Ladakh and ended in an uneasy truce. The two countries have been trying to settle their border dispute since the early 1990s, without success.

India unilaterally declared Ladakh a federal territory and separated it from disputed Kashmir in August 2019, ending its semi-autonomous status. The move further strained the relationship between New Delhi and Beijing, which raised the issue at international forums including the U.N. Security Council.

In a symbolic move, India banned some Chinese-owned apps, including TikTok, about two weeks after the deadly clash, citing privacy concerns that it said pose a threat to India’s sovereignty and security.