Zambia's new President Michael Sata announced plans to overhaul the constitution on Friday, the latest step in his top-to-bottom review of the way Africa's top copper producer is run.

Sata did not give details about what he wanted to change although much of his September election victory was built on a platform of re-balancing the economy in favour of local investors rather than foreigners.

He said the government would appoint a committee to come up with a new nationally acceptable constitution for Zambia within 90 days.

Foreign investors, especially in the key mining sector, have been nervous about what policies Sata would introduce but he said any changes would be preceded by consultations.

At the opening of parliament on Friday, Sata criticised the policies of the previous government for stifling local enterprise.

This has been largely due to lopsided policies of the previous government, which tended to favour foreigners at the expense of local investors, he said, adding he would encourage joint ventures between foreigners and locals.

While Zambia will continue to welcome foreign direct investment, it must be understood that the most sustainable and lasting investment must come from Zambian people, he said.

Sata won the presidency largely supported by the youth and said he owed young people jobs and would introduce programmes that empowered them.

Part of his plan is to lower interest rates at commercial banks, although he did not give a time-frame.

Currently, Zambia does not use a key lending rate as a monetary policy tool but has been talking about introducing it since 2009.