The Yemeni Socialist Party (Arabic: الحزب الاشتراكي اليمني, romanized: al-Ḥizb al-Ishtirākī al-Yamanī; YSP), also known as the Socialist Party Organization (منظمة الحزب الاشتراكي, Munaẓẓamat al-Ḥizb al-Ishtirākī), is a political party in Yemen. The successor of the National Front, it was the sole legal political party in South Yemen until the Yemeni unification in 1990. Originally Marxist–Leninist, the party has gradually evolved into a social democratic opposition party in today's Republic of Yemen.
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