* Curve tracks Ukraine-driven energy price rises

* Cal '15 price highest since April 30

* Nearby German wind output to decline

FRANKFURT, June 16 (Reuters) - European power forwards on Monday traded higher in reflection of firmer gas prices, which responded to the unresolved row between Europe's main gas supplier Russia and transit country Ukraine over unpaid bills.

"Clearly the uncertainties must be priced into power but don't forget that prices had been low, so this morning's advances are not surprising," a curve trader said.

The German Cal 2015 baseload power contract for next-year delivery was up 63 cents from Friday levels at 34.83 euros ($47.4) per megawatt-hour, a near seven-week high after 34.95 euros on April 30.

The bid-ask range of the equivalent French contract was 42.13 euros, up 12 cents from Friday.

After unsuccessful weekend discussions in the long-standing row, Russia's Gazprom said Ukraine had failed to pay at least part of its gas debts by a 0600 GMT deadline and would now have to pay up front for deliveries, suggesting that supplies could be cut.

Generators factor in prices of gas and coal as they show the cost of feedstock for thermal power, and also carbon emissions rights which are levied on burning fuels for electricity.

The oil price, the energy sector's "lead currency", also plays a sentiment role for power. Brent crude held near nine-month highs as violence in Iraq is rising, intensifying concern over potential disruption to exports from the second-largest OPEC exporter.

Apart from reflecting the Ukraine uncertainty, UK and continental gas also firmed in tandem with oil.

Nearby power was also firmer, boosted by cooler weather and less wind. The German baseload power contract for delivery on Tuesday, at 34 euros, was 1.50 euros up from levels paid for Monday.

The equivalent French contract was 5.9 euros up at 35.9. .

Thomson Reuters Point Carbon data showed that daily wind power output will fall 40 percent to 2.2 gigawatts on Tuesday day-on-day.

The weather is cloudy and cooler than in recent days, German met office DWD said in a note, pointing out that Monday temperatures lag those seen at the weekend by 4 degrees Celsius, but adding that temperatures would recover by Tuesday/Wednesday.

Power usage in mainly Catholic regions this week will be curbed by the Corpus Christi holiday on June 19 and the bridge day June 20 as industrial power requirements fall when manufacturers and offices close.    ($1 = 0.7345 Euros) (Reporting by Vera Eckert; Editing by Dale Hudson)