DOHA June 18 (Reuters) - Three Qatari companies and Iraq's National Investment Commission have agreed to develop $9.5 billion worth of projects in Iraq, including the construction of a pair of power plants that will generate a total of 2,400 megawatts, according to statements issued on Sunday.

UCC Holding and the investment commission on Thursday signed a 25-year public-private partnership linked to the two power plants, which will cost $2.5 billion to build, a statement issued by UCC Holding said.

The power plants will help reduce Iraq's reliance on neighbouring Iran for its energy needs.

Iraq imports electricity and gas from Iran, which in total makes up between a third and 40% of its power supply, especially crucial in the sweltering summer months when temperatures can top 50 degrees Celsius (122°F) and power consumption peaks.

Iraq's investment commission and Doha-based Estithmar Holding also signed deals worth $7 billion to manage hospitals, develop two "new comprehensive cities" and to build a series of new 5-star hotels totaling 10,000 rooms, a statement issued by Estithmar said.

"The cities ... will include residential complexes, villas, schools, commercial complexes, entertainment centers, and other facilities and services, in addition to all the infrastructure needed to build these cities," Estithmar vice-chairman Ramez Al-Khayyat said in the statement.

It is unclear how much money either the Qatari companies or Iraq's investment commission will commit to these projects.

The agreements were signed during a visit to Baghdad by Qatar's ruling emir on Thursday, when he pledged to make a $5 billion investment in Iraq. (Reporting and writing by Andrew Mills Editing by Mark Potter)