Long a key provider of light, sweet crude from the African continent, Nigeria is suddenly the increased focus of many of the world's Big Oil companies as they try to renew production leases on fields they have worked for years.

As last week came to a close, ExxonMobil (NYSE:XOM) reached an agreement with the government for three leases. The new leases carry terms of 20 years, with options for renewal.

Not long ago, several of the major Western integrated oil companies became alarmed when Nigeria's government said it had been approached by Chinese interests that wanted to acquire interests in the licenses that were held by the Western companies, but were about to expire. It later became apparent that China's state-owned CNOOC (NYSE:CEO) had its eye on as many as 20 Nigerian blocks, including some that were not up for renewal.

As The Wall Street Journal pointed out on Monday, however, at least in part because of the long-standing relationships between Nigeria and the Western companies, the Chinese never stood much of a chance of scooping up the leases. As such, people familiar with the talks between the government and the companies contend that the Chinese threat has essentially disappeared.

Nevertheless, the companies remain eager to complete the next round of licenses. It seems that the government is considering reworking the legislation in a way that would magnify the taxes and royalties paid by the companies. Shell's (NYSE:RDS-A) still-new CEO Peter Voser last month met with Umaru Yar'Adua, the president of Nigeria. As the Journal noted, Shell executives in attendance emphasized that "they had been long-term investors in Nigeria and shouldn't be forced out of the country's oil fields now."

Chevron (NYSE:CVX), which also has licenses up for renewal, was attracted to Nigeria, along with the likes of Total (NYSE:TOT) and Eni (NYSE:E), thanks to the nation's high-quality crude.

The renewed commitment to Nigeria comes as it has fallen to second place among oil-producing African nations, behind Angola. Chevron and BP (NYSE:BP) made significant discoveries in Angola's offshore region, and the country doesn't suffer from the same attacks and kidnappings as installations in Nigeria. Although the militant MEND group that was largely responsible for the decreased production from the Niger Delta has been temporarily placated, it will be interesting to see how long a truce will last if the underlying issues of rampant poverty, failing schools, and a lack of jobs are addressed.

My takeaway from events in the volatile West African country is that, while I can't claim any special knowledge behind ExxonMobil's having renewed its contracts first, in the world of Big Oil, the company almost always seems to come in first. I wouldn't let that tendency be lost on Foolish investors with an inkling for energy. 

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