Youth groups in Taiwan are marking the anniversary of a movement that occupied the island's parliament and scuttled the ratification of a trade pact with its biggest trade partner and erstwhile political foe, China.

A rally outside parliament Wednesday evening followed by an overnight event Sunday will draw new attention to what has become known as the Sunflower Movement, which handed Taiwanese President Ma Ying-jeou his toughest crisis since taking office in 2008.

Stung by the occupy movement and tens of thousands of sympathy protesters, Ma's Nationalist Party lost nine local elections in November, prompting him to resign as party head.

Protests last year also dealt a blow to Taiwan's relations with China, which had improved under Ma but remain tense.