Qatar pledged Monday to shore up Lebanon’s ailing economy by buying $500 million’s worth of governments bonds, a move that muscles in on rival Saudi Arabia’s role as Beirut’s financial patron.

Qatar’s bond buying is part of a diplomatic and business offensive undertaken since Saudi Arabia and three other countries cut off diplomatic ties and imposed an economic boycott on Doha in June 2017. The Saudi-led group says Qatar promotes extremism in the region and is too closely aligned with Iran—charges that Qatar has denied.

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