AMSTERDAM, Jan 12 (Reuters) - The Dutch government said on Friday it had no certainty yet over the planned sale of electricity grid operator TenneT's German division to the German state.

Both governments have negotiated for months over the sale, but have failed to reach an agreement so far, the Dutch Finance ministry said in a letter to parliament. The Dutch government said it would lend TenneT up to 25 billion euros ($27.4 billion)through 2025 to fulfill its investment needs. ($1 = 0.9124 euros) (Reporting by Bart Meijer)