Naxiketa, as you're in India, I'm not too sure about what kind of ants you get, but certainly in general, ants are only present on plants because there are aphids present - the ants collect the honeydew the aphids excrete. Therefore, if you get rid of the aphids, you get rid of the ants, but any normal run of the mill insecticide should clear the aphids. You are best using a systemic insecticide because that means they'll be kept away for up to 10 days, but if you don't want to risk that, try eco friendly washing up liquid diluted in water and spray with that. Do not use ordinary washing up liquid, that's worse than using a proper insecticide, and do not use any washing up liquid neat - mix it about 1 or 2 parts to ten parts water in a sprayer. You will need to apply a solution like this every day, probably, because it only kills the aphids it touches, whereas systemic insecticide enters the sap stream of the plant and continues working for up to 10 days or so.

hi you could always try perfumed talcumn powder for the ants not sure about the aphids though.

Spinosad baits kill ants without harming pets or wildlife. Aphids will probably need frequent and thorough spraying with an organic soap solution, such as a natural dishwashing liquid, or commercial insecticidal soap. Neem oil also frequently helps with aphids, mainly as a preventative, though it will slowly reduce the population by keeping the babies from maturing.