Starwood’s plans to add robot butlers to its workforce has been branded a “gimmick” by a UK workers’ union, which says the hotel chain should instead focus on taking better care of its existing staff.

The US-based hospitality giant is currently testing out the machines and has indicated that robot butlers could be used in as many as 100 hotels worldwide.

The machine in question – named Botlr – is capable of shuttling items such as towels, razors and phone chargers from the lobby to guests’ rooms, before returning to its charging station to await further orders. Starwood says the labour saving device – developed by Silicon Valley-based start-up Savioke – would free up human staff to spend more time on other activities.

But Hugh O'Shea, spokesperson for workers’ union Unite, said the hotel giant should focus on other priorities.

"With a night at one of Starwood's luxury London hotels costing around £290 (US$482, €362), the global hotel chain would do better ditching the gimmicks and investing in better pay and training programmes for its worldwide workforce," O'Shea told the BBC.

"Starwood Hotels' 'butler robots' are a nifty little gimmick but can't ever replace the human touch expected by discerning hotel guests."

The robots, which slightly resemble Star Wars character R2-D2 in a butler’s collar, are currently being tested by Starwood at its Aloft Hotel in Cupertino, California.

The hotel company – which runs chains such as St Regis, W Hotels and Le Meridien – has been quick to emphasise that the bots are not intended to replace entry level jobs, with one Starwood executive describing them as “an enhancement to our customer service.”

Although nowhere near human capability so far, robots are appearing more and more in the leisure industry. The Tate Modern recently launched an initiative, whereby camera-clad robots serve as virtual tour-guides, taking internet users on an after-hours tours of the gallery, with web users able to control the robots and customise their viewing experience.