Kelis is craving tomatoes during her pregnancy.

The 'Milkshake' hitmaker - who already has son Knight, six, with her former rapper husband Nas - is expecting her second child with an unknown father and this time she cannot get enough of the red fruits, which her next door neighbour leaves outside her house for her and she eats simply with salt and pepper sprinkled on.

She said: ''I'm pregnant! I'm so excited! It's really amazing. ''My neighbour grows tomatoes and leaves them on my doorstep and I'll cut them up, use salt and pepper, and just eat them like that!''

While she is enjoying tomatoes, the 36-year-old singer instantly develops cravings for any other foods people mention in conversation.

She told US Weekly magazine: ''I'm very open to the power of suggestion. If someone talks about a certain food, my pregnancy brain gets so focused and I have to have it!''

Kelis gushed about how ''excited'' Knight is to become a brother and how bringing out a cookbook 'My Life on a Plate' along with the new baby means it's ''a really exciting time'' for all of the family.

She added: ''My son is excited to be a brother and I'm thrilled. With my cookbook coming out and a new baby, it's a really exciting time for us.''

Kelis revealed she was pregnant on stage at Afropunk Festival in Brooklyn, New York last month.

A source previously shared: ''She had a great time at Afropunk this weekend and will continue to perform as long as she feels good.''