By Adaobi Tricia Nwaubani

ABUJA (Thomson Reuters Foundation) - Women's rights activists urged the Nigerian Senate on Wednesday to take action after a male senator was reported by local media to have threatened to assault and impregnate a female colleague.

Senator Dino Melaye told his female colleague Senator Oluremi Tinubu that he would assault and impregnate her after a dispute during a closed session of the Senate last week, according to a coalition of 46 Nigerian civil society groups.

"I will beat you up, impregnate you and nothing will happen," Melaye was quoted as saying by Nigerian media.

In a public statement last week, Melaye said he had been provoked by Tinubu, who he claims called him "dog" and "thug", but denied using abusive or degrading language against her.

"It is fallacious, malicious and a lie that I said I will impregnate Remi Tinubu. Biologically it is even impossible to impregnate her because she has arrived at menopause," he said.

Senate officials were not immediately available for comment.

The incident comes just months after the Senate threw out a gender and equality law that pledged to eliminate discrimination in politics, education and employment, protect women's rights and tackle violence against women.

The rejected bill also called for women to be able to participate in politics without any restrictions or barriers - in a country where only seven of the 109 senators are women.

The Legislative Advocacy Coalition on Violence Against Women (LACVAW) said it would protest outside the National Assembly and deliver a petition demanding a response from Nigeria's Senate.

"(Melaye's language) empowers abusive men outside the Assembly to believe that violent and threatening behavior towards women can continue unabated," the coalition said.

"Melaye's assertion that 'nothing will happen' after his abuse of Tinubu is a blatant manifestation of the general impunity pervading violence in Nigeria, especially against women," the LACVAW said in a statement before it delivered its petition.

The coalition said Melaye's language and threats broke an anti-violence law passed last year, and other campaigners said the government's duty to protect women and girls in Nigeria included dealing with the senator's behavior in parliament.

"Our future and that our children depend on the actions we take now, and we must put an end to this recurring act of violence, abuse and threats," the Lagos branch of the Bring Back Our Girls activist group said in a statement.

In a separate incident in April, the head of Nigeria's prisons service was summoned before parliament after his security guards allegedly slapped a female lawmaker, Joan Onyemaechi Mrakpor, according to Nigerian media.

(Reporting by Adaobi Tricia Nwaubani, Writing By Kieran Guilbert, Editing by xxxxx; Please credit the Thomson Reuters Foundation, the charitable arm of Thomson Reuters, that covers humanitarian news, women's rights, trafficking, corruption and climate change. Visit news.trust.org)