Miners in Africa's top copper producer Zambia may have to scale down in the face of a move to raise royalties by the new government of President Michael Sata, the general manager of the country's chamber of mines said on Monday.

The increase in mineral royalty will significantly raise costs for the mining companies ... Each mine will have to examine its own cost structure and depending on the impact of the higher tax some may decide to shut down certain sections, Frederick Bantubonse told Reuters.

In the first budget since September's election upset, Finance Minister Alexander Chikwanda put flesh on the bones of new President Michael Sata's promises to spread the benefits of strong growth in Africa's biggest copper producer.

Overall spending would rise to 27.7 trillion kwacha ($5.5 billion), or 26.5 percent of gross domestic product (GDP), from 21 percent in 2011, Chikwanda said.

Domestic borrowing for the year would amount to 1.3 percent of GDP and foreign financing would be 3.0 percent, giving an overall deficit of 4.3 percent of GDP, Chikwanda said. Foreign aid would amount to less than 2 percent of GDP.