General Motors Corp. accelerates talks with a number of parties interested in its Saturn brand and dealer network, as the auto maker tries to whittle down to four core brands.

“GM will be reviewing expressions of interest from the potential buyers and will look to secure an agreement with a specific buyer later this year,” the auto maker says in a statement released today.

Mark LaNeve, vice president-sales, service and marketing at GM North America, says “a lot of interested parties” would like to buy Saturn Distribution Corp. “We’re hopefully optimistic,” LaNeve told Ward’s during a conference call last week to discuss GM’s April sales results.

Outside of Telesto Ventures, an investor group that includes private-equity firm Black Oak Partners LLC, as well as a number of Saturn dealers, the other parties have not been identified.

Telesto says it is interested in the 19-year-old Saturn brand and its 400 dealers, but only would source vehicles from GM for a short period before pursuing products from other global manufacturers.

The new Saturn would concentrate on smaller, more fuel-efficient vehicles, a strategy almost certain to kill the Outlook large cross/utility vehicle GM presently builds at its Delta Twp., MI, assembly plant.

In addition to the Outlook, Saturn’s current portfolio includes the Astra compact car imported from GM’s Adam Opel GmbH unit in Germany; Aura midsize sedan built in Fairfax, KS; Vue midsize CUV from Ramos Arizpe, Mexico; and Sky roadster assembled in Wilmington, DE.

GM has retained S.J. Girsky & Co. as an adviser for a Saturn transaction. Girsky, a former auto industry analyst at J.P. Morgan Chase & Co., worked for GM as a special adviser several years ago.

GM earlier this month announced plans to phase out the Saturn division by the end of the year, if it did not reach a satisfactory agreement with a buyer. Hummer and Saab also will be discontinued if no buyers are found, although Saab Automobile reportedly could be lumped together with Opel if Fiat Auto Group is successful in its bid for the German auto maker.

GM also will shutter the Pontiac brand by the end of 2010, so it can focus its resources on Chevrolet, Cadillac, Buick and GMC.

GM has sped up the restructuring of its brands at the behest of President Obama’s auto industry task force, which rejected a viability plan the auto maker filed March 30. Surviving on $15.4 billion in taxpayer loans, GM now has until June 1 to right-size its business or face bankruptcy.

The latest restructuring will take GM down to four brands for the first time since 1909, when it added Cadillac to go along with Buick, Oldsmobile and Oakland.