Krishna spoke to Thinley and sought Bhutanese assistance in the search operations along the Indo-Bhutan border, sources said.
The two also discussed the issue of logistical support to people involved in the search operations, they said.
Meanwhile, Indian Ambassador to Bhutan Pavan Verma said that the operations were being done by the Indian Government and the Bhutanese authorities were providing all cooperation.
“Since yesterday the Bhutanese have been most cooperative," he said.
The four-seater single-engine Pawan Hans helicopter AS-B350-B-3 chopper went missing yesterday after 20 minutes of its take off from Tawang at 9.56 am last morning with five on board including crew members Captain JS Babbar, Captain TS Mamik, Khandu"s security officer Yeshi Choddak and a lady Yeshi Lhamu, sister of Tawang MLA Tsewang Dhondup.