Saudia will launch flights to Toronto and Los Angeles in the third quarter of 2013 and the second quarter of 2014 respectively.
The Saudi flag carrier says it will deploy the four 777-300ERs that it is due to receive by the end of 2013 - part of a 20-aircraft order - on the Los Angeles route.
Its North American expansion plans will also see capacity increases on its 14 weekly services to Washington and New York, which will be operated with larger aircraft from April 2013.
Separately, Saudia has plans to launch 11 weekly flights to Paris with a 777-200, including four from Riyadh and seven from Jeddah.
It will further operate 14 flights to Geneva in summer 2013, comprising seven weekly flights each from Riyadh and Jeddah.