By Zaffar Abbas BBC correspondent in Islamabad

Pakistan has made more changes to the country's election laws which are aimed mainly at keeping former prime minister Benazir Bhutto out of the electoral process.

Anyone convicted by a court because of their failure to appear before it in a corruption case is now barred from contesting the October elections.

Earlier, another amendment in the laws prevented any former prime minister from running for a third term.

This disqualifies Ms Bhutto as well as former prime minister Nawaz Sharif, both of whom have served two terms.

Opposition critical

Since the announcement of general elections in October this year, the military-run government has introduced several changes to the electoral procedure.

The government says these changes will improve the country's democratic system.

Opposition parties have, however, criticised most of these new laws and say they amount to pre-poll ballot rigging.

Before the latest amendment, only people convicted on charges of criminal offences were barred from becoming members of parliament.

Critics say President Musharraf is trying to hold on to power

Benazir Bhutto, who lives abroad in self-imposed exile, is the only prominent opposition politician to be affected by the new law.

She has been sentenced to a three-year jail term because of her failure to appear before a court in a corruption case.

Ms Bhutto's Pakistan People's Party has described it as a person-specific law and says it shows the government is determined not to allow her to stand in the elections.

One of the other amendments made in the election laws goes in favour of religious minorities.

Their members will not only be allowed to stand in the elections but a specific number of their representatives will also be elected to the national and provincial assemblies through indirect votes.

The government has also withdrawn proposed changes in the election procedure for the upper house of the parliament, the Senate.

As was the case in the past, its members will be elected by the four provincial assemblies.