It said studies have shown there has been no adverse impact on economic growth from wages increases so far.
Somkiart Chayasriwong, permanent secretary for labour and chairman of the tripartite Central Wage Committee, yesterday said the wage panel decided to uphold its resolution on Nov 2 last year to raise the daily minimum wage to 300 baht across the country.
The 300-baht wage hike was earlier implemented from April 1 this year in seven provinces _ Bangkok, Nonthaburi, Samut Prakan, Samut Sakhon, Nakhon Pathom, Pathum Thani and Phuket.
Mr Somkiart said the minimum wage would go up to 300 baht across the country from January but there would be no further increases in 2014 and 2015.
He said the panel has closely monitored the economic situation following the increase in April, and found that the economy kept expanding and that the inflation and unemployment rates remained under control.
The panel plans to forward the countrywide wage hike for cabinet approval soon as it wants the new rate to be put in place in January after it is published in the Royal Gazette.
The 300-baht daily minimum wage policy was a major part of the ruling Pheu Thai Party's campaign platform during last year's elections.
Mr Somkiart said second-quarter gross domestic product grew by 4.2%, higher than that in the first quarter, as a result of increased purchasing power.
In the past few months, inflation has been recorded at 2.92%, lower than the estimated 3.3-3.5%, he said.
The unemployment rate between January and June was 0.8%, which was not high, the wage panel chairman said.
He added that about 80% of small-and medium-sized enterprises (SMEs) had been affected by the wage boost.
However, 99% of them were able to adjust to the situation, he said, citing a survey jointly conducted by the Labour Ministry, the Thai Chamber of Commerce and the Federation of Thai Industries.
A study has also shown that the wage increase has helped boost labour efficiency by 8.7% over the past seven months, he said.
The government has put in place measures to cushion the impact of the wage increase on business operators.
These include a temporary reduction in employers' monthly contributions to the Social Security Fund and the offer of low-interest loans to SMEs.
Attayuth Leeyavanich, secretary-general to the Consumer Products and Services Employers Council, criticised the committee's decision to raise the minimum wage throughout the country, saying it would have a greater impact on the economy than the April hike.
The panel should have put the issue on its agenda to allow all sides to debate it, he said.
He rejected Mr Somkiart's claims about economic growth, saying there was only economic uncertainty.
Wilaiwan sae Tia, vice-chair of the Thai Labour Solidarity Committee, agreed with a nationwide wage increase, but strongly opposed the panel's decision not to lift it again until after 2015.
Most workers would suffer in that time period as inflation and consumer goods prices would keep rising, she said.
Rojjanin Phatchararuangkij, managing director of Smile Heart Foods in Samut Sakhon, said the wage rise in January will have only a limited impact on his firm, which produces frozen seafood mainly for export.
The company has brought in machinery and has trained workers to be more productive, the managing director said, adding that the hike will motivate the workers to work harder.
Federation of Thai Industries secretary-general Sommat Khunset said the National Wage Committee should postpone the launch of nationwide wage boost until at least 2014.
Mr Sommat said the best time to implement a nationwide hike is between 2014-2016 to allow SMEs time to adjust.
Many SMEs are still reeling from the effect of the earlier increase, which has also pushed up inflation, he said. These problems have not been effectively tackled so far, and the January rise would only compound their troubles.