India said on Thursday its relationship with China was at a crossroads with the months-old military standoff in mountainous border areas profoundly disturbing the ties.

“Peace and tranquillity in the border areas is the basis for the development of relations in other domains,” External Affairs Minister Subrahmanyam Jaishankar said in a speech at a conference discussing India-China ties. “If they are disturbed, so inevitably will the rest of the relationship.”

“Choices that are made will have profound repercussions, not just for the two nations but for the entire world,″ Jaishankar said.

Indian and Chinese soldiers brawled again last week in the Naku La area of northeastern Sikkim state. Last year, 20 Indian troops died in a clash with Chinese soldiers using clubs, stones and fists in another portion of the disputed border. China is believed to also have had casualties, but has not given any details.

Jaishankar said that with exchanges growing steadily in the past decades, China became one of India’s largest trading partners, a significant source of investment and technology and a participant in projects and infrastructure building as well as a substantial destination for tourism and education.

He said that to date India has yet to receive a credible explanation for the change in China’s stance or reasons for the massing of troops in border areas.

“It is a different matter that our own forces have responded appropriately and held their own in very challenging circumstances,” he said.

There was no immediate comment from the Chinese government.

The standoff has continued despite nine rounds of meetings involving local military commanders and political dialogue by foreign and defence ministers.

Both sides have mobilised tens of thousands of soldiers, artillery and fighter aircraft along the fiercely contested border known as the Line of Actual Control that separates Chinese and Indian-held territories from Ladakh in the west to India’s eastern state of Arunachal Pradesh, which China claims in its entirety.

India and China fought a war in 1962.