BUCHAREST, Sept 1 (Reuters) - Romania"s centrist Prime Minister Florin Citu sacked his justice minister Stelian Ion on Wednesday, accusing the junior government partner of undermining local communities" development plans, a move that could threaten reform. A rupture in the coalition made of Citu"s Liberal Party, Ion"s USR and the ethnic Hungarians group, which jointly control 56% of parliament, could endanger the government"s agenda to curb twin deficits and fight the pandemic, leaving it without a majority and prone to concessions. Even before the coronavirus pandemic, Romania was struggling with a widening budget shortfall from years of political instability and fiscal largesse under previous leftist cabinets that have worried the European Commission. "I will not accept ministers in the Romanian government who oppose the modernisation of Romania," Citu told a late night news briefing. "Blocking the activity of the government only because you do not agree to develop the communities, means violating the mandate given to you by parliament through the governing programme." Citu was trying to approve a 50 billion lei ($12 billion) local development infrastructure financing scheme aimed at modernising decrepit infrastructure in the countryside and the plan needed justice ministry"s seal of approval. Ion"s USR has said the plan has been marred by flaws. "Tonight, Prime Minister Florin Citu has just shown that he has no respect for the law, for the Constitution," Ion said. ($1 = 4.1654 lei)