The United States took the first step towards a full-blown trade dispute with India Wednesday on the solar power sector, the World Trade Organisation said.

A WTO statement said that Washington had requested consultations over what it claims is unfair support for India's solar cell and solar panel producers.

Requesting consultations is the first move that WTO members must take before launching a full suit at the global body, which aims to ensure a level playing field in international commerce.

The WTO said that the United States alleged that India requires solar power developers to purchase and use solar cells and solar modules of domestic origin in order to be able to take part in the country's solar energy programme.

"As a result, the US alleges, solar power developers, or their successors in contract, receive certain benefits and advantages, including subsidies through guaranteed, long-term tariffs for electricity, contingent on their purchase and use of solar cells and solar modules of domestic origin," the WTO said.