WARSAW, June 22 (Reuters) - Polish construction firm Polimex-Mostostal said on Friday it had signed a letter of intent with GE Power for the joint construction of a 1,000 megawatt (MW) unit at the Ostroleka power plant, sending its shares 13 percent higher.
Poland's energy minister has said the Ostroleka unit built by state-run utilities Energa and Enea will be the last coal-fired power station built in Poland.
In April GE Power, together with Alstom Power, won a tender to build the unit in northeast Poland with a bid of 6 billion zlotys ($1.62 billion).
A consortium of Polimex-Mostostal and Rafako failed to win the tender with a bid worth 9.59 billion zlotys as did China Power Engineering Consulting Group, which offered 4.85 billion zlotys.
In May a GE Power executive told Reuters that it might subcontract Polimex and Rafako for the project.
The letter of intent between Polimex and GE Power is valid until September 30.
At 1427 GMT Polimex shares were up over 10 percent. ($1 = 3.7064 zlotys) (Reporting by Agnieszka Barteczko Editing by Alexander Smith)