* Saipem deal seen worth 2.5 billion euros - source
* Novatek wants new LNG plant running by 2022-2023
* Export credit agency SACE to offer guarantees - source
By Katya Golubkova and Stephen Jewkes
MOSCOW/MILAN, Dec 18 (Reuters) - Italian energy contractor Saipem SPMI.MI plans to sign a deal this week with Novatek NVTK.MM to build offshore platforms for the Russian firm's liquefied natural gas project, Arctic LNG 2, two sources close to talks told Reuters.
Novatek aims to produce as much LNG as Qatar, one of the world's top LNG suppliers that exported 6.2 million tonnes in November. Novatek has one plant in operation and Arctic LNG 2 on the Gydan Peninsula in the Kara Sea will be its second.
The first plant, Yamal LNG, began running at its full capacity of 16.5 million tonnes of LNG a year this month.
This week, Novatek issued tenders to build an airport for Arctic LNG 2 and to recruit its personnel. sources close to the talks said Saipem and Novatek planned to sign a firm deal in Italy this week for the construction of gravity-based structure (GBS) platforms that will stand on the seabed to support the LNG processing units.
One of the sources said Italian export credit agency SACE planned to issue guarantees to support development of the Arctic LNG 2 project. The Saipem-Novatek deal had an estimated value of about 2.5 billion euros ($2.9 billion), the source said.
In 2016, SACE and French export credit agency COFACE provided insurance cover for the 750 million euro loan issued by Italian bank Intesa ISP.MI for Yamal LNG.
SACE would not comment on any support for Arctic LNG 2. "We have an excellent relationship with Novatek. Our plan is to support Italian companies involved in the Arctic project to be developed in coming months," a SACE spokeswoman said.
Saipem declined to comment and Novatek did not reply to a Reuters request for a comment.
Novatek plans to start producing LNG at Arctic LNG 2 in 2022-2023, with production of 19.8 million tonnes a year when at full capacity. Arctic LNG 2 is estimated to cost $25.5 billion, compared with Yamal LNG's $27 billion price tag.
French energy major Total TOTF.PA has already agreed to buy a 10 percent stake in the project. Saudi Aramco is also among those interested in a minority stake. = 0.8776 euros)