Plum and Nectarine Sangria

3 plums, halved, pitted and cut into thin wedges 

3 nectarines, halved, pitted and cut into thin wedges 

1 can (12 fl. oz.) nectarine nectar 

1/4 cup orange liqueur 

1 bottle (750ml) dry white wine  

Ice cubes as needed 

1 bottle (24 fl. oz.) sparkling water, chilled