What's his feeding routine look like? If the meals are too close to his bottles, he may not be hungry enough to eat. Toddlers' appetites decrease a LOT after their first birthday, so some routine adjustment might be in order.
Have you tried finger foods? A lot of times, toddlers just want a bit of independence, and finger foods or using their own utensils can help. Choices are good too. Offer only two things and let him choose which one he wants. If he isn't verbal yet, he can still point or gesture. If he chooses not to eat, that's his choice too.
He's old enough to understand how to make food into a battleground, and he can probably sense your concern. My best advice to you is to relax a bit and try to keep mealtimes as low key as possible. Eating meals with him might help some, if you aren't already, and I'd cut out the distractions. If he chooses not to eat, try to lightly say something like "I guess you aren't hungry right now, maybe later" and end the meal. A lot of time if you remove the pressure to eat and the attention that's being paid to the situation, the problem resolves itself.
I always say that healthy babies don't starve themselves, but if you are concerned about his weight loss then a call to the dr might be in order.
