Civil society groups in Nigeria Thursday called for fresh hardship protests next week against President Bola Tinubu's economic policies, fuel price hikes and soaring living costs.

They have called for a nationwide rally on October 1, coinciding with the anniversary of Nigerian independence 64 years ago.

Chanting protest songs, organisers vowed at a press conference in the economic hub Lagos to continue to march against "anti-people" policies.

Last month, protests tagged #EndbadGovernanceinNigeria took place across major cities.

At least 21 people were killed by Nigeria's security forces, according to Amnesty International.

Police say seven people died, but commanders say the police and army were not responsible for any deaths.

The protest in "August was a dress rehearsal, the one on October 1 is a continuation," Hassan Taiwo, of the Education Rights Campaign, told reporters.

Organisers demand a reduction of fuel and food prices, electricity tariffs and the release of protesters arrested in August, among other things.

Since coming to power last year, Tinubu has ended a costly fuel subsidy and freed up the naira currency in reforms that analysts say will revive the economy and attract investors.

But in the short term, Nigerians have seen fuel prices soar and inflation hit a three-decade high.

"Less than two years ago, a litre of fuel did not cost more than 200 naira (about $0.12, 0.11 euro)" Taiwo said.

Prices now vary between around 855 naira ($0.52) and 1,200 naira per litre, depending on the supplier and location.

"As a direct consequence of this increment, life has become unbearable for many Nigerian people."