South Korean President Moon Jae-in's approval rating hit a record low since he took office in May last year, a weekly survey showed Thursday.

According to the Realmeter poll, support for Moon retreated 5.2 percentage points over the week to 58.0 percent this week.

Moon's support rate stayed at a relatively high level, but his support scores fell below 60 percent for the first time since his inauguration.

President Moon ordered a temporary cut in electricity rate earlier this week amid the scorching heat wave that hit the entire country, but it failed to meet public expectations.

Public calls mounted for the revision of the incremental electricity bill system, which is only applied to households.

Households are required to pay more electricity charges in an incremental basis, the more power they use. It requires households to bear more burden for power rate than industrial companies and merchandisers.

Support for Moon's ruling Democratic Party shrank 2.7 percentage points over the week to 40.1 percent this week.

The main conservative opposition Liberty Korea Party won 19 percent of support, up 1.4 percentage points from a week earlier.

The minor progressive Justice Party kept its record-breaking trend for the third consecutive week, with 14.5 percent in support scores.

The minor conservative Bareun Future party won 5.3 percent of support, and the centrist Party for Democracy and Peace garnered 2.2 percent in approval rating.

The results were based on a survey of 1,507 voters conducted from Monday to Wednesday. It had 2.5 percentage points in margin of error with a 95 percent confidence level.