THE confrontation between Nigeria's military regime and civilian opposition has deepened as striking oil workers continued to stay away in defiance of a government order to return to work.

Ignoring the government sacking of their leaders, oil workers from the Nupeng and Pengassan unions stepped up their strike yesterday to demand a return to civilian rule and recognition of the result of last year's election.

They found some solace in the courts, where Mamman Kolo, a federal high court judge, ordered the reinstatement of the sacked union leaders. He said they should remain in office until their appeal against dismissal can be heard on 31 August.

Reports on Monday said that the oil strike seemed to be cracking after General Sanni Abacha, the military ruler, gave them till today to return to work or be sacked. But yesterday the strikers stayed away in even greater numbers as the strike went into its eighth week. One executive of a multinational oil company said: 'On Monday some came in; yesterday even fewer people turned up. Today there's no one.'

About 98 per cent of Nigeria's foreign exchange comes from oil exports and the strike has cut back previous production levels of 2 million barrels per day by more than a fifth. The government, which owns 52 per cent of the oil companies, has stopped paying a share to their multinational partners. Shell, for example, is owed more than dollars 800m ( pounds 516m) by Nigeria and is threatening to cut back on exploration. A fuel shortage within the country is bringing transport and industry to a halt.

Inflation was running at over 60 per cent before the oil strike and is now thought to be far higher. The government's response has been to climb deeper into its bunker. Hopes of a deal between General Abacha and Moshood Abiola, the man generally accepted to have won last year's election, have faded. Although Mr Abiola fled Nigeria after his election was declared void by the military government a year ago, support for his presidency grew. After he declared himself president in June on the anniversary of his election, the government put him on trial for treason.

Support for Mr Abiola, who comes from the south-west, has grown and spread throughout the country, though it remains strongest in his home base, and weakest in the north, which has always provided Nigeria's leadership, military or civilian.

To purge his high command of waverers, General Abacha has removed southerners and Christians who are thought to be willing to support a deal to return the country to civilian rule. On Monday he sacked the head of the army and navy and replaced them with loyalists.