NEW DELHI (AFP) - US aviation authorities have downgraded India's safety ranking in a "disappointing" and "surprising" move that will hit air links between the countries, India's aviation minister said on Friday.

The US Federal Aviation Administration downgraded India after conducting an audit last year of India's aviation regulator that found 31 areas of concern, a statement said.

The areas of concern include better recruitment and training of professional and technical staff for India's aviation regulator, responsible for the safety of the country's airlines, the statement.

"They have downgraded us to category 2, which is very disappointing and also surprising," Aviation Minister Ajit Singh said at a press conference in New Delhi.

The minister said 95 per cent of issues raised by the FAA have been resolved, while the remainder were expected to be resolved by March, adding it was the first time India had suffered a downgrade.

The downgrading effectively bars Air India and Jet Airways from increasing flights to the US and additional safety checks will now be imposed on existing flights to the United States, the FAA's wesbite shows.

Indian airlines will also have to snap ties with US airlines, according to the website. Jet has a code-share agreement with United Airlines currently while Air India is joining Star Alliance.

The downgrade is the latest controversy between the US and India which are attempting to put diplomatic relations back on track after outrage in December over the arrest and strip search of an Indian envoy in New York.