In the face of the hostage-taking crisis in Nigeria's oil-rich Niger Delta region, the government has pledged to improve security in a bid to stem the growing threat to Africa's biggest oil industry.

The last three years have seen an upsurge in violent attacks and kidnappings targeting oil companies in the unruly Niger Delta, the country's oil heartland.  Some were carried out by militants claiming to be fighting for a greater share of the region's oil wealth for local people, others by criminal gangs out to make ransom money.

Oil workers say they could no longer tolerate the situation and may go on strike unless the government improves security in the region.

Petroleum Minister of State Odein Ajumogobia says the government is committed to improving security in the southern oil region.

"The security services are doing their best to try and address the issue," Ajumogobia said.  "We are appealing to the oil workers to bear with us.  We are trying to provide as much security as we can to make the facilities safe to work in.  I do not think going to strike is the solution, because that just disrupts the entire economy and everybody is affected.  So, I am not sure that is the solution.  Government is doing everything it can to address the issue of insecurity."

The unrest has reduced Nigeria's oil output by a quarter since 2006.   The largest oil producer in Nigeria, Royal Dutch Shell, warned last week that unrest in the Niger Delta meant it may be unable to meet some oil export obligations from its Bonny terminal for the next couple of weeks.

A panel set up by the government said in December that Nigeria should direct 25 percent of its oil revenue to the Niger Delta and release the leader of the region's main militant group if it is to achieve peace in the Niger Delta.

President Umaru Yar'Adua promised when he came to power 20 months ago to quickly address the unrest, free jailed militants and engage the rebels in talks.  But there has been little tangible progress since then.