Tanzanian opposition MP Zitto Kabwe and a coalition of local civil society organisations have written to the World Bank urging it to withhold a pending loan to the government because of human rights concerns.
In 2018 the bank withheld a $300m (£230m) loan meant for improving secondary education after President John Magufuli ordered pregnant schoolgirls be banned from attending school.
Another reason given for not approving the loan was the passing of a law to jail people who question official statistics.
The statistics law was amended last year to remove the threat of jail but the government has yet to announce changes to the rules on teenage pregnancy.
In September 2019 the World Bank approved the release of the money with the first tranche expected in weeks.
"I am asking that you suspend lending to this government until basic checks and balances are restored in Tanzania," Mr Kabwe said in a letter to the World Bank.
He highlighted the jailing of journalists, especially that of Erick Kabendera, and the harassment of opposition members among reasons the bank should consider.
"The World Bank faces a choice: It can affirm gender equity, the rights of girls and women, human rights and the rule of law," the Concerned Citizens of Tanzanian Civil Society said in a statement.