The bill, which contains penalties of up to 14 years in prison and bans gay marriage, same-sex "amorous relationships" and membership of gay rights groups, was passed by the national assembly last May but Jonathan had delayed signing it into law.
Two similar bills have been proposed since 2006 but failed to make it through parliament.
"Yes, Mr President had signed the bill into law, a statement will be issued on it within the week," presidency spokesman Reuben Abati said.
As in much of sub-Saharan Africa, anti-gay sentiment and persecution of homosexuals is rife in Nigeria, so the new legislation is likely to be popular. Jonathan is expected to seek re-election in 2015 but is under pressure after several dozen lawmakers and a handful of regional governors defected to the opposition in the past two months.
Under existing Nigerian federal law, sodomy is punishable by jail, but this bill legislates for a much broader crackdown on homosexuals and lesbians, who already live a largely underground existence. » | Felix Onuah | Tuesday, January 14, 2014
