The Arjan Garh metro station in New Delhi is getting a colourful makeover with the help of two urban artists from Singapore.

The young women - Samantha Lo, 31, and Soph Ong, 33 - said they drew inspiration from nature for their mural, which is named "Aasha", or hope.

"Painting the metro is a big honour," Lo told The Straits Times recently as she and Ong took a short break from their work. "Looking at how big the space is... It's a massive opportunity."

When completed, the mural featuring local greenery and birds such as a giant kingfisher will cover the facade of the metro station, which sits on top of a busy road that connects New Delhi to the satellite city of Gurugram.

The project is part of a collaboration between St+art India foundation and the Delhi Metro Rail Corporation to provide "art for everyone". The rail corporation has installed artworks at half a dozen metro stations.

"(The) flora and fauna are native to both Singapore and Delhi... Before the metro was built, there was just this land. We wanted to bring back that remembrance," said Lo, better known as "Sticker Lady" after she stencilled "My Grandfather Road" on several Singapore roads and pasted stickers bearing captions such as "Press Once Can Already" on traffic light buttons.

"We are city kids from Singapore and we are constantly being exposed to development... We want to preserve what it was before. We are also drawing a parallel between the birds and commuters as both are always passing by," she added.

Pointing to a little alien peeping out of a bird known as a green bee-eater on one wall, Ong said they included this element after she read about India's space programme.

The two artists are working with a group of Indian volunteers who help with the painting. The Singapore High Commission and Singapore Tourism Board in New Delhi are also lending their support.

"The Arjan Garh metro station project is exciting as it brings together Singapore and Indian artists to explore this theme from their unique artistic and cultural perspectives. We hope the completed work will bring colour and life to the surrounding neighbourhoods," said Mr Lim Thuan Kuan, Singapore's High Commissioner to India.

"As vibrant, ever-growing cities, Delhi and Singapore face similar challenges of balancing between preserving nature and urbanisation. Singapore has adopted the concept of a 'City in a Garden' as we strive to introduce more greenery into our urban landscape."

The two artists were about to resume painting when they spotted an elephant, a rare sight in New Delhi nowadays. They rushed off to snap some photos, and soon they were back at work.

"Time is our biggest challenge," said Lo, who has been clocking 10-hour shifts with Ong amid a heatwave in the city.