He made his view known at a meeting of the party yesterday (12) chaired by prime minister Ranil Wickremesinghe to discuss the next moves following the election.
According to Marapana, the Sinhala-Buddhist vote base of the UNP suffered by the day, losing 50,000 votes every time the Tamil version of the national anthem was sung.
Media minister Mangala Samaraweera responded to his claim animatedly.
Meanwhile, minister Sajith Premadasa said the UNP lost a chance to move closer to the public due to its not having the Samurdhi ministry, and proposed to the PM to immediately take over that ministry.
Minister P. Harrison remarked that a main reason for the defeat in rural areas was the non-availability of fertilizer for farmers.
However, minister Patali Champika Ranawaka challenged the claims by Premadasa and Harrison and stressed the need to safeguard the Sinhala Buddhist vote base.