AFP - A marathon 171-hour concert of Frederic Chopin's music tuned up in Warsaw Monday marking the two possible birthdates of celebrated Franco-Polish musician and composer 200 years ago.

"As we don't know which of the two dates is true, we had the unusual idea to link them with one very long concert," organiser Pawel Besser from Centrum Smolna cultural association told AFP.

Records point to either February 22 or March 1 as Chopin's birthdate.

More than 250 musicians and singers are to play night and day over the 171 hours spanning the seven-day gap between the two dates, he said.

While Chopin's certificate of baptism indicates February 22, 1810, as his birthday, Chopin himself and his family always mentioned March 1 as his actual birthdate.

"A genius can have a week-long birthday," Waldemar Dabrowski, head of the organising committee for Poland's "Year of Chopin" said recently.

Over the week spanning February 22 to March 1, the Warsaw Philharmonic will also hold daily concerts devoted to Chopin featuring artists such as Murray Perahia, Ivo Pogorelic, Nelson Goerner, Janusz Olejniczak, Rafal Blechacz, Kevin Kenner, Daniel Barenboim, Nikolai Demidenko and Evgeni Kissine.

On March 1, Chopin concerts by Garrick Ohlsson, Leif Ove Adsnes, Yundi and Dang Thai Son will be held at Warsaw's royal castle and at the composer's birthplace in Zelazowa Wola, some 60 kilometres (37 miles) west of the Polish capital.

After having spent the first 20 years of his life in his homeland, Chopin left just before the November 1830 Polish insurrection against Tsarist Russia.

Initially he lived in Vienna before moving to Paris, where he died at the age of 39 on October 17, 1849.