AMMAN—Saudi Arabia and its Gulf allies pledged $2.5 billion in support of Jordan’s monarchy after mass protests over economic grievances roiled the country, sparking fears of another Arab Spring.

After a meeting in the Saudi city of Mecca, Saudi Arabia, the United Arab Emirates and Kuwait in a joint statement early Monday said that money includes a deposit in Jordan’s central bank, funding to support the country’s budget for the next five years, World Bank guarantees and financing of development projects.

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