NEW DELHI: India and the US will attempt to firm up a long-negotiated agreement which will provide for obtaining critical and encrypted defence technologies by the Indian military from the US, official sources said.

They said discussions on finalising the Communications, Compatibility, Security Agreement (COMCASA) will be one of the key focus areas of the '2+2' talks between India's foreign and defence ministers with their US counterparts here on September 6.

Both sides are committed to move forward on COMCASA as it will further bolster defence and strategic cooperation between the two countries, the sources said.

"The effort will be to thrash out the differences on COMCASA," said a source, without elaborating on sticky issues.

Though COMCASA will facilitate India to obtain critical defence technologies from the US, there have been apprehensions here about allowing the US access to sensitive military communication network.

The agreement will facilitate access to critical communication network to each other to ensure interoperability among the US and the Indian armed forces.

It will also allow the installation of high-security US communication equipment on defence platforms being sourced from the US, the sources said.

The defence and security cooperation between the US and India is on an upswing in the last few months.

Last month the US announced granting India the status of Strategic Trade Authorisation-1 (STA-1) country, the only South Asian nation to be given the designation along with the US' NATO allies like South Korea, Australia and Japan.

The STA-1 status will help India get critical technology from the US in the defence and certain other key areas.

The move is expected to further facilitate India-US trade and technology collaboration in defence and high technology areas.

Currently there are 36 countries on the STA-1 list. Till recently India was designated as STA-2 countries, along with seven others.

In June 2016, the US had designated India as "Major Defence Partner" intending to elevate defence trade and technology sharing with India to a level commensurate with that of its closest allies and partners.