The western province remained as the highest contribution to GDP in 2009 but its share reduced further to 45.
1 percent from 45.4 percent in 2008, it said in an analysis of provincial GDP.
The contribution of the northern province to the GDP improved slightly to 3.3 percent in 2009 compared to 3.
2 percent in 2008.
"This was a positive development that may be observed since the ending of the 30-year old conflict," the statement said.
"There was no significant expansion of the contribution of the northern province to GDP as the impact of the improvement in consumer and investor confidence in the aftermath of the civil war will only be felt by the economy with a time lag."
The island's ethnic conflict ended in May 2009 when Tamil Tiger separatists were defeated by government forces, resulting in an immediate upturn in the national economy as hitherto unproductive regions came back into production.
The northern and eastern regions were the worst affected by the war.
The eastern