Volgograd, site of the decisive battle at which two million died, is controversially restored to its former name for a few days a year

The southern Russian city where the Red Army turned back Nazi forces in a pivotal second world war battle will once again be known as Stalingrad - at least on the days commemorating the victory.

The city was renamed Volgograd in 1961 as part of the Soviet Union's rejection of dictator Joseph Stalin's personality cult. But the name Stalingrad is inseparable from the battle, which was among the bloodiest in history with combined losses of nearly 2 million people.

The decision by regional lawmakers to use the historic name in city statements on 2 February, the day of the Nazi defeat, as well as on several other war-related dates each year, has angered many in Russia where Stalin's name andlegacy continues to cause fiery disputes nearly 60 years after his death. Russia's human rights ombudsman, Vladimir Lukin, sharply criticised the move, saying it should be declared void in the courts.

"This is an insult of the memory of those who died," he said, according to the Interfax news agency.

Nikolai Levichev, a senior federal lawmaker with the leftist Just Russia party, condemned the restoration of the old city name, saying "it's blasphemous to rename the great Russian city after a bloody tyrant who killed millions of his fellow citizens." Levichev added that the country won the war "despite rather than thanks to" the leadership of Stalin, whose errors multiplied the Soviet losses.

Stalin led the Soviet Union from 1924 until his death in 1953. Communists and other hardliners credit him with leading the country to victory in the second world war and making it a nuclear superpower, while others condemn his purges, during which millions were murdered.

President Vladimir Putin, a former KGB officer, has avoided public praise or criticism of Stalin, but he has restored Soviet-era symbols and tried to soften public perceptions of the dictator. Others have seen attempts to whitewash Stalin's image as part of Putin's rolling back of democracy.

In recent years, many in Russia were outraged by government-produced school textbooks that portrayed Stalin in a positive light and the reconstruction of a Moscow subway station that restored Soviet national anthem lyrics praising Stalin, as part of its interior decoration.

In addition to the Volgograd legislature's decision to temporarily restore the name Stralingrad, authorities in Volgograd, St. Petersburg and the Siberian city of Chita have ordered that images of Stalin decorate city buses on February 2 to commemorate the battle.

Yan Raczynski of Memorial, a leading Russian human rights group, was quoted by Interfax saying that the authorities' moves highlighted the nation's failure to "legally and politically recognise the crimes committed by the Bolshevik regime, particularly Stalin and his inner circle".

Communists said the decision to restore the name of Stalingrad for just a few days each year is a half-step. Communist lawmakers met World War II veterans and sent a letter to Putin urging the government to rename the city once and for all, the party said in a statement.

But Sergei Zheleznyak, a politician for United Russia, the party that dominates the Duma, said there were no plans to do so.

On Saturday, Russia will mark the 70th anniversary of the battle, which raged for six months over the winter of 1942-43. The Red Army fought the Nazis hand to hand before encircling and capturing more than 100,000 German soldiers.