How to select an option in the list of Angular JS?

There is such code:

<select name="city" ng-model="formData.city"> <option ng-repeat="(key, value) in data.cities" value="{{key}}">{{value}} </option> </select> 

The variable formData.city number 1723 is the number of the city.

In the data.cities object data.cities all cities:

 {1723: "Baru"} 

How to highlight in the list the optics with a value of 1723