* German econmin says it's crucial ECB returns to mandate quickly
* ECB declines to comment
* Econmin says Germany does not believe in debt-financed stimulus
* Econmin faces crucial election in home state at weekend (Adds details, background)
BERLIN, Jan 16 (Reuters) - Germany's economy ministry urged the European Central Bank on Wednesday to get back to its price stability mandate as soon as possible after its extraordinary support measures to tackle the euro zone's troubles.
"Monetary value must be stable for prices to be able to fulfil their signalling function," the ministry said in its annual report.
"That's why the European Central Bank has a clear mandate: the ultimate goal of monetary policy is to ensure price stability. It is therefore crucial for the ECB to return to its normal mode of monetary policy as quickly as possible."
Germany continues to campaign for economic and financial policies throughout the euro zone to be devised in such a way that a swift return to conventional monetary policy is possible, the report said.
The German government does not generally comment on ECB policy and tends to point to the central bank's independence instead, though Economy Minister Philipp Roesler has repeatedly broken with this tradition. He also made a similar call on the ECB to exit crisis mode in the economy ministry's April report.
While the ECB declined to comment on Roesler's statements, ECB President Mario Draghi suggested at a monthly news conference last week that the central bank would not be abandoning its crisis measures any time soon: "We are not thinking about an exit now," he said.
The euro zone's debt crisis has prompted the ECB to resort to extraordinary measures such as buying struggling states' bonds and pumping low-cost money into the economy. In September it announced a new and potentially unlimited bond-buying programme which has yet to be tapped.
A Reuters poll this week showed a small majority of money market traders believed the ECB probably would not make use of the bond-buying scheme for struggling euro zone governments this year.
STIMULUS FOR SPAIN?
Spanish Prime Minister Mariano Rajoy said in the Financial Times on Tuesday that while Spain did not need to use the ECB's bond-buying programme now, he would not rule out asking for aid in the future.
Rajoy also said euro zone creditor countries should do more to stimulate growth when it is needed.
Asked about these comments, Roesler said: "We do not believe in debt-financed economic packages ... What we have introduced on a European level has the express aim of making growth possible in all European countries, in the euro zone."
Roesler warned the ECB last July against any large-scale government bond purchases.
Roesler is also leader of Germany's Free Democrats (FDP), Chancellor Angela Merkel's junior coalition partner, who sometimes get poll ratings under the 5 percent they would need to re-enter parliament after general elections later this year.
If his party fails to clear the 5 percent threshold to enter the assembly in an election in his home state of Lower Saxony on Jan. 20, calls for him to resign will likely get louder.
A Forsa poll on Wednesday gave the FDP just 3 percent and analysts said Roesler was attempting to drum up support with his comments about the ECB, particularly from eurosceptic quarters.
"I think everything Roesler is saying should be viewed through his party's glasses and through the election," said Carsten Brzeski, senior economist at ING in Brussels.
"When it comes to European policy measures, there are only two people to listen to at the moment: Merkel and (Finance Minister Wolfgang) Schaeuble. This is just pleasing party people and voters." (Writing by Michelle Martin in London; additional reporting by Madeline Chambers in Berlin and Paul Carrel in Frankfurt; editing by Stephen Nisbet)