Operation Fish was the relocation of British money and gold ingots from the United Kingdom to Canada for safekeeping during the Second World War. It was the largest known movement of physical wealth in history.

The Moscow Gold, or alternatively Gold of the Republic, was 510 tonnes of gold, corresponding to 72.6% of the total gold reserves of the Bank of Spain, that were transferred from their original location in Madrid to the Soviet Union a few months after the outbreak of the Spanish Civil War. This transfer was made by order of the government of the Second Spanish Republic, presided over by Francisco Largo Caballero, through the initiative of his Minister of Finance, Juan Negrín. The term also encompasses the subsequent issues relating with the gold's sale to the USSR and the use of the funds obtained. The remaining quarter of the Bank's gold reserves, 193 tonnes, was transported and exchanged into currency in France, an operation which is also known by analogy as the "Paris Gold".