Puchong Nutrawong, EC secretary general, also corrected another false report that ballots were printed in excessive numbers.
He acknowledged having problems in organising the advance election in some southern provinces this Sunday due to a shortage of 50,000 personnel to be stationed at polling booths.
He asked for cooperation from all ministries, departments and the armed forces and said personnel from other agencies might be assigned to work at polling booths.
Candidacy registration failed to take in 28 constituencies in eight southern provinces.
The EC viewed that a royal decree is needed to hold elections in the 28 constituencies after the Feb 2 general election, said Mr Puchong.