Sienna Miller loves wearing ''masculine workman's clothes''.

The 35-year-old actress is currently ''drawn'' to ''big, baggy'' garments that resemble ''chimney-sweeper trousers'', but the blonde-haired beauty has admitted she has no idea where her interest in the androgynous style has stemmed from.

Speaking to WWD about her fashion favourites, Sienna - who has four-year-old daughter Marlowe with her former partner Tom Sturridge - said: ''I don't really know where it came from, but I'm quite into quite masculine workman's clothes. I keep getting drawn to big, baggy, sort of chimney-sweeper trousers and tweeds. High-waisted, bunched-up things and slightly odd shoes.''

However, the 'American Sniper' star has revealed her wardrobe has changed from being ''quite flirty and sexy'' in the past to now adorning ''do-not-fancy-me'' clothes.

Speaking about her style evolution, the New York-born star - who has starred in campaigns for designer brand Burberry - said: ''I used to be quite flirty and sexy, and now it's just like, 'Do-not-fancy-me' clothes.''

But Sienna prefers to look ''unattractive'' and have as little flesh on show as possible.

She added: ''The more unattractive I can make myself, the less flesh I can possibly show, the better.''

Meanwhile, Sienna - who has recently been announced as the face of Swedish company Lindex - has revealed her ultimate favourite fashion label is Chloé, although she may ''hate'' an item until she sees the label and then she becomes ''obsessed'' with it within a matter of moments.

The 'The Lost City of Z' star - who portrays Nina Fawcett in the drama film - said: ''I can hate it [a product] and see it's got that [Chloé] label and be obsessed with it in a second.''