The protest began on Monday morning, when some of the miners refused to leave the mine after the end of their shift.
Trade unions have said the action is spontaneous, and is not a strike, as coal continues to be extracted.
The protesting miners are calling for the government to extend the programme of layoff compensation to their mine.
Earlier this month, parliament approved a bill on the functioning of the hard coal industry, which envisages severance packages for miners being laid off by state-owned mines.
This does not include PG Silesia, which is a private company.
According to the trade unions, on Tuesday afternoon some 30 miners were continuing their protest underground and a few more at an aboveground facility.
Trade union leaders appeared at a press conference with presidential aides Karol Rabenda and Mateusz Kotecki, who earlier met underground with the protesting miners.
The head of the Solidarity trade union at PG Silesia, Grzegorz Babij, read out a letter sent by Energy Minister Miłosz Motyka.
Motyka asked the miners to suspend their protest for the festive period and return to talks with the government after January 6.
The minister added that officials were "working intensively on finding legislative ways to offer support to PG Silesia workers."
He said the government needed to "verify possibilities for offering assistance under national law and in line with state aid rules."
Babij called the letter "a punch in the face for PG Silesia miners."
He added: "The government has been analysing things for months. The bill has already been passed and they're still analysing ... I am asking 'how much longer? Do they want me to show this scrap of paper to people underground?"
Meanwhile, President Karol Nawrocki has announced he would table an amendment to the hard-coal industry law to extend layoff compensation to PG Silesia miners.
His aide Rabenda told the news conference the energy minister was being "cowardly" and was also trying to "con" the miners as the government had previously offered severance packages to workers leaving privately owned energy firms and lignite companies.
Rabenda warned that Motyka's stance was "pushing the protesters, their families and other workers to a certain radicalism which we would all probably like to avoid."
Unionists told reporters that the protesters would remain underground unless they received written assurances that the government would accept the president's amendment to the hard-coal industry law, extending layoff compensation to PG Silesia miners.
The protesters also called on their employer to immediately start talks over the situation at the company and guarantees for workers.
Motyka said in a post on the X platform on Monday that "PG Silesia is currently undergoing restructuring, and companies in that process are not eligible for state aid under existing law."
Motyka added the government was examining ways to support the mine’s workers and had filed a motion to conclude the restructuring proceedings, after which further steps could be taken.
Based in the southern town of Czechowice-Dziedzice, PG Silesia is Poland's largest private coal mine. In 2022, it produced 2.3 percent of the country's hard coal output.
In late November, PG Silesia's official receiver notified the trade unions of planned mass layoffs.
Under the plan, some 750 employees are to be made redundant, Polish state news agency PAP reported.
(pm/gs)
Source: PAP