NEW DELHI (REUTERS) - India conferred one of its highest civilian awards on billionaire philanthropist and Microsoft co-founder Bill Gates and his wife Melinda for their work to improve health in developing countries.

The announcement was made by the Indian government on Monday after Prime Minister Narendra Modi hosted US President Barack Obama for a Republic Day parade, a day after they held talks to deepen ties between the world's two largest democracies.

Every year the Padma Bhushan award is presented to Indians and some foreigners for service in various areas.

US citizen Gates, whose Bill and Melinda Gates Foundation has poured billions of dollars into medical research in developing countries, has partnered with the Indian government, aid groups and the private sector to curtail the spread of HIV in the country.

The world's wealthiest foundation has also expanded into tackling maternal and child health and nutrition in India.