* State-run firm's CEO might be fired - source, newspapers
* CEO did not agree to help other state-run firms - papers
* Energy minister, JSW decline to comment
* Minister says agenda for board meeting not approved yet
* JSW shares fall 8.5 pct (Adds more energy minister comments)
By Agnieszka Barteczko
WARSAW, Sept 10 (Reuters) - Poland's energy ministry plans to fire the chief executive of state-controlled miner JSW at a supervisory board meeting on Thursday following disagreements over strategy, a company source told Reuters on Monday.
Newspapers Rzeczpospolita and Dziennik Gazeta Prawna earlier reported that JSW might dismiss CEO Daniel Ozon this week, sending shares in the European Union's biggest coking coal producer down as much as 8.5 percent.
The papers said Energy Minister Krzysztof Tchorzewski had pressed Ozon to take over construction company Polimex from other state-run companies, including gas firm PGNiG and utilities PGE, Enea and Energa , which helped rescue Polimex from collapse last year.
"I was pressed many times to finance with JSW money investments which are completely unrelated with JSW operations. As the CEO, I am to take care of the company, its development and shareholders," Rzeczpospolita quoted Ozon as saying.
Dziennik Gazeta Prawna said the minister had also wanted JSW to help finance the construction of a coal-fueled power plant in Ostroleka, northeast Poland, built by Energa and Enea.
"At the moment it is difficult for me to talk about the potential change of the CEO. There is an audit at JSW. At this stage I do not understand the CEO's behaviour," Tchorzewski told Reuters in a telephone interview, referring to Ozon's comments to Rzeczpospolita.
He declined to say whether Ozon would be fired this week, adding the agenda for the supervisory board meeting had not been agreed yet.
Tchorzewski also said he was not engaged in any talks regarding JSW's potential investment in Polimex.
A JSW spokeswoman declined to comment.
Trade unions at JSW sent an open letter to Tchorzewski and prime minister Mateusz Morawiecki, defending the CEO and protesting against his potential dismissal.
"JSW cannot be a life ring for other companies that are not doing well," they said in the letter.
Last week, Reuters reported JSW was considering a purchase of Australia's Prairie Mining.
Poland's ruling Law and Justice party (PiS) has made sweeping changes to the management of state-run companies since coming to power.
Ozon was appointed JSW's CEO in November 2017. (Reporting by Agnieszka Barteczko; Editing by Mark Potter)