The conservative CDU easily retained its majority

Support for the SPD fell by one third to 30.8%. The conservative Christian Democrats (CDU) retained a majority in the state assembly with 47.5%.

In the European elections in June, the SPD suffered its worst result in decades.

The government's hated economic reforms have been blamed for the defeat.

These include controversial cuts in social welfare payments.

Saarland, with its coalmining past, was an SPD stronghold until 1999.

Far-right gains

CDU national leader Angela Merkel - likely to challenge Mr Schroeder for the chancellorship in 2006's general elections - described the result as "sensational".

Schroeder has vowed to continue his economic reforms

The SPD state leader, Heiko Maas, conceded the result was a "clear and bitter defeat", but party officials insisted there was no going back on the government's economic programme.

Though the CDU retained its absolute majority in the statehouse, it increased its proportion of the vote by only two percentage points.

Smaller parties emerged as the real gainers in the elections.

The far-right National Democratic Party came from nowhere to take 4.2% - just a fraction short of the 5% needed to take parliamentary seats.

The Greens and pro-business Free Democrats both crossed the 5% hurdle.

Turnout dropped substantially in the poll, from 69% in 1999 to 55.5%.

Resistance to reforms

The 800,000 voters appear to have punished the SPD for Germany's sluggish economy and Chancellor Schroeder's extremely unpopular attempts to reform it, says the BBC's Ray Furlong in Berlin.

The government's economic reforms are deeply unpopular

Tens of thousands of people have marched against cuts in welfare and unemployment benefits over recent weeks.

Mr Schroeder has already suffered a string of setbacks in local, state and European elections earlier this year.

The SPD has now been defeated in six out of the seven state elections held since early 2003, when Mr Schroeder embarked on his reforms.

Later this month he is also staring defeat in the face in elections in two East German states - Brandenburg and Saxony - says our correspondent.