Turkish President Abdullah Gul signed into law late on Wednesday a long-sought revision of a law criticised by the EU for limiting free speech in Turkey, a candidate for EU membership.

The reform to article 301 of the penal code was published in the Official Gazette and took effect yesterday. The reform was approved in Parliament last month amid fierce criticism from the nationalist opposition.

The article has been used to prosecute hundreds of writers, including Nobel Literature Laureate Orhan Pamuk, for "insulting Turkishness".

The reform makes it a crime to insult the Turkish nation, rather than Turkishness, and the justice minister's permission will be required to open a case. The maximum sentence is cut to two years from three.

The EU has said easing restrictions on free speech is a test of Turkey's commitment to political reform as Ankara looks to advance slow-moving membership talks which began in 2005.

Armenian-Turkish editor Hrant Dink, shot dead by an ultra-nationalist youth last year, had been convicted under article 301.