LAGOS, June 4 (Reuters) - One of Nigeria's main oil and gas unions is holding off from recalling workers from offshore rigs pending the outcome of talks between government and labour unions on Tuesday over a new minimum wage, the union chief said.

On Monday, Nigeria's main labour unions shut down the national grid and disrupted flights across the country as they began an indefinite strike over the government's failure to agree a new minimum wage.

Nigeria, Africa's largest oil producer, relies on the oil and gas for around 90% of foreign exchange earnings and about half for its budget.

The Nigeria Union of Petroleum and Natural Gas Workers (NUPENG) directed its members to comply with the indefinite strike called by Nigeria's two biggest workers union federations. (Reporting by Isaac Anyaogu Writing by Chijioke Ohuocha Editing by Andrew Cawthorne and Louise Heavens)