The moderate Islamism advocated by the AKP was at odds with the secular establishment of the Republic of Turkey. While serving as the Mayor of Istanbul, Erdoğan was sentenced to a 10 month prison term in 1998 for reciting a poem in Siirt for which he was accused of inciting racial intolerance. This barred him from initially seeking a seat in parliament, meaning that the AKP's co-founder Abdullah Gül became Prime Minister following their election victory. With the help of the CHP, the government overturned Erdoğan's political ban in 2003, after which he was able to seek a seat in a controversial by-election in the Province of Siirt. Erdoğan became Prime Minister in March 2003, with Abdullah Gül concurrently assuming the role of Foreign Minister and Deputy Prime Minister.