"Fortunately, there is something in copyright law called 'Classics protection'. This means that the Swedish Academy … has the right to protest in court the use of 'literary and artistic works … that violate cultural interests. This is what we will do now," stated Swedish Academy Permanent Secretary Peter Englund in a blog post on Friday.

The advert which has caused Englund and the Academy to react has been created by advertising agency ANR for German luxury car brand Mercedes Benz and features Swedish actress Lena Endre reading a poem by Karin Boye.

Boye was a Swedish poet and novelist who died in 1941. The poem which features in the advert is her perhaps most well-known work "On The Move" (I rörelse). 

"Move on, move on! The new day is dawning. 

Endless is our great adventure," the poem ends.

Englund in his blog post argued that the fact that Boye has been dead for over 70 years does not excuse what he described as "a gross distortion of both the poem and what the author once stood for".

He explained that Boye was a keen advocate of socialism and surmised therefore that she would never have approved of the use of her work in this manner.

"Exploiting Boye's poem in this insensitive and thoroughly commercialized way is grave robbery," Englund argued, revealing that the Academy has sent a cease and desist letter to the German car firm's Swedish headquarters.

Neither ANR nor Mercedes Benz had replied publicly to the letter by Saturday morning but ANR project leader Fredrik Pantzerheim told the Expressen daily in a previous interview that the firm had sought permission from the Karin Boye society the last time they used the poem in an advert, for car firm Renault.