South Korea's SK Engineering & Construction said on Tuesday that a joint venture it operates with a US company had signed a $3.5 billion deal to build a petrochemicals complex in Egypt at Ain Sukhna, an energy hub on the Gulf of Suez. The unlisted South Korean builder said in a statement that it and US engineering company Shaw Group plan to construct the complex from 2012 to 2016 under the agreement made with Egyptian private company Carbon Holdings.