French energy companies Total SA (TOT) and GDF Suez SA (GSZ.FR) Tuesday said they have signed a draft agreement to acquire half of the Kazakh national oil and gas company KazMunaiGas' 50% stake in the Caspian Sea Khvalinskoye exploration license, building up their respective positions in the region.

Total plans to take a 17% stake and GDF Suez 8%, the companies said.

A spokeswoman for GDF Suez declined to say how much the companies would pay for the stake. Total didn't immediately return a request for comment.

Russia's Lukoil (LKOH.RS) is the operator of the Russian-Kazakh project, in which it has 50%.

The agreement gives Total "the opportunity to further strengthen its ties with KazMunaiGas," said Yves-Louis Darricarrere, Total's head of exploration and production, in a statement.

Total and the Kazakh national company are already partners in developing Kazakhstan's giant Kashagan oil field, also in the Caspian sea.

The move also would open a new front in Total's growing links with Lukoil. Both companies have said they want to develop their partnership, under which Lukoil recently took a stake in a Total-operated refinery in the Netherlands.

Last month, Lukoil said it and Total were considering joint exploration projects in Kazakhstan, Colombia and western Africa.

For GDF Suez, the move underscores the company's strategy of boosting its exploration and production activities to increase the amount of gas it produces.

The Khvaliskoye project straddles the border between Russia and Kazakhstan, a GDF Suez spokeswoman said.

GDF Suez said the project would be its first in Russian exploration and production.

"It will also reinforce GDF Suez's position in the exploration and production activities in the Caspian region, following the recent acquisition of a 20% stake in the Absheron license in Azerbaijan," GDF Suez also said.

The agreement heralds an "exclusive negotiation phase" and is "subject to relevant partners' and authorities' approvals," GDF Suez said.

-By Adam Mitchell, Dow Jones Newswires, +33 1 40171756; adam.mitchell@dowjones.com