The United States is ready to help resolve the dispute between India and China over the mountain border running through the western Himalayas, US President Donald Trump said on Friday.

Both sides deployed additional forces along the frontier after a clash in June, during which 20 Indian soldiers were killed in hand-to-hand fighting agencies reported.

The defence ministers of India and China held talks in Moscow on Friday, the highest level face-to-face political contact since tensions flared along the disputed mountain border in May.

In the meeting, Chinese defence minister Wei Fenghe told his Indian counterpart Rajnath Singh that New Delhi bears full responsibility for the current border tensions, according to China’s state-backed Global Times newspaper.

India’s defence ministry tweeted that the meeting lasted for 2 hours and 20 minutes, without giving out further details.

Trump, asked about the dispute at a news briefing in the White House, said Washington was talking with both countries about what it could do to help defuse the situation.

Trump has offered to mediate between the two nuclear-armed nations in the past. China has said that there is no need for a third party to mediate and India has also appeared cool to the idea.