Vijay's Mallya's son, Siddharth, is working on the Guinness brand after gaining a place on Diageo's graduate trainee scheme.

Siddharth Mallya, 21, joined Diageo's graduate scheme in September and is currently working as an assistant brand manager on Guinness, a Diageo spokesperson confirmed to just-drinks today (22 January).

The move strengthens ties between Diageo and India's United Spirits, which is part of billionaire Vijay Mallya's UB Group.

It is known that Diageo CEO Paul Walsh has a good relationship with Mallya senior, who has been hailed as India's answer to UK business tycoon Richard Branson.

Diageo and United Spirits have spent recent months weighing up the potential for some form of collaboration in India, which could possibly see Diageo taking a stake in the Indian group.

However, talks have so far not progressed beyond a preliminary stage, just-drinks understands.

Diageo already has a joint-venture in India with Radico Khaitan, which it would likely have to dispose of for any deal with United Spirits. Khaitan has a 10% share of India's spirits market, compared to United Spirits' estimated 60% share.

A report in India's Economic Times this week cited unnamed sources as saying that Khaitan has sought to sell a 26% stake of its business to a number of international drinks groups.