Sienna Miller looks summer chic in red floral mini dress as she runs errands with fiancé

Sienna Miller looks summer chic in red floral mini dress as she runs errands with fiancé Lucas Zwirner

She has perfected the bohemian chic look. 

And Sienna Miller proved her fashion sense is still on top form as she wore a scarlet floral dress in New York City on Monday. 

The Layer Cake actress, 38, was busy running errands with her toyboy fiancé, Lucas Zwirner, 29, who she became engaged to in January after just one year of dating.

Keep it simple: Sienna Miller perfected the bohemian chic look on Monday as she walked through NYC with her toyboy fiancé, Lucas Zwirner 

She was captured on the streets of the Big Apple wearing a short red floral number that showed off her slender physique. 

Sienna accessorised the outfit with a pair black shades and a simple yet stylish brown bucket bag from Loewe.

Keeping things simple and practical, she wore black sandals and a face mask to ensure she was protected. 

The actress kept her blonde tresses in a natural wave and opted for a makeup free look as she maintained her signature bohemian style. 

An item: The thespian, 38, conversed in the middle of the Big Apple with her art dealer fiance, Lucas Zwirner, whom she met in 2019 and is nine years her junior

An item: The thespian, 38, conversed in the middle of the Big Apple with her art dealer fiance, Lucas Zwirner, whom she met in 2019 and is nine years her junior

Sienna was joined on the outing by her art dealer lover, Lucas, who is nine years younger than her.

He also kept things simple as he cut a casual fit in a pair of cobalt blue jeans and a muted brown t-shirt. 

The Yale-educated literature expert is the son of famed art dealer David Zwirner.

He joined the family business to grow his father’s eponymous art gallery, David Zwirner Books, where he currently oversees the publication of 25 book releases per year.

He reportedly dropped down on one knee earlier this year, and has been spotted at several high profile events with his leading lady. 

Sienna attended a pre-Met Gala event in 2019 with her beau and they have also attended several high-profile weddings such as the nuptials of singer Ellie Goulding and Caspar Jopling where the pair were seen laughing alongside Princess Beatrice. 

Sienna has a daughter whom she shares with her actor ex-fiancé, Tom Sturridge, 34.

She also had an on-off romance with her Alfie co-star Jude Law and got engaged to him on Christmas Day in 2004 but called off their engagement in 2005 after he confessed to having an affair with his former children’s nanny. 

They would reunite again in 2009 but only to break up for the final time in 2011.

Rocky road: The Alfie actress experienced an on-off relationship with her co-star Jude Law and was betrayed by the star when he revealed he had an affair with his child's former nanny

Rocky road: The Alfie actress experienced an on-off relationship with her co-star Jude Law and was betrayed by the star when he revealed he had an affair with his child’s former nanny