President Salva Kiir has taken a softer stance towards a U.N. vote to send in extra troops

* Security Council has voted to send extra troops

* Kiir's spokesman initially said that would be opposed

* President now says final decision still not taken (Updates with HRW's report on atrocities)

By Denis Dumo

JUBA, Aug 15 (Reuters) - South Sudan will consider a United Nations plan to send in troops and stop the country's episode of violence, President Salva Kiir said on Monday, confirming a softer stance towards a U.N. vote to send in extra troops.

The U.N. Security Council authorised an extra 4,000 troops on Friday, something Kiir's spokesman immediately said the government would oppose. On Sunday, however, the information minister said the proposal would be considered.

"There are people who are accusing the transitional government of refusing and fighting the U.N. ... this is not accurate," Kiir said at a ceremony to reopen parliament.

"The transitional government has not met to declare its final position. Deliberations will come later on a final position," he said, without saying when the government might make a decision.

The U.N. decision was a reaction to days of fierce fighting in Juba, the country's capital last month. The violence raised fears of a slide back into civil war in the world's youngest nation, which gained independence in 2011.

Human Rights Watch (HRW) said it had uncovered evidence of cold-blooded execution of civilians, including a journalist, by security forces during last month's fighting. The group also found evidence of civilians being raped by soldiers in the chaos of the fighting, it said on Monday.

The U.N. made similar accusations against the military earlier this month.

HRW criticised the U.N. for failing to impose a "long overdue arms embargo", calling for asset freezes and travel bans on those who carried out abuses. "The continued supply of arms only helps fuel the abuses on a larger scale," said Daniel Bekele, the group's Africa director.

Ateny Wek Ateny, the president's spokesman, said he could not comment since he was still going through the report.

Earlier, Kiir had said in his speech to parliament they were investigating reports of sexual assaults, calling them unacceptable.

At least two civilians and a soldier were killed in fighting southwest of the capital on Saturday between Kiir's forces and troops loyal to his former deputy, Riek Machar. Each side blamed the other for starting the violence.

The extra U.N. troops, described as a protection force that has the backing of African nations, will fall under the command of UNMISS, the existing 12,000-strong U.N. mission.

The U.N. resolution threatens South Sudan with an arms embargo if it does not cooperate.

Kiir said the government had serious concerns about the U.N. decision but was willing to discuss them to find the best way of "achieving our mutual interests".

Political differences between Kiir and Machar first erupted into conflict in late 2013. A peace deal ended the civil war in August 2015, but sporadic fighting continued.

Machar withdrew with his forces from Juba after violence flared in July, setting up a potential armed standoff.

(Writing by Duncan Miriri; Editing by Robin Larry King)

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