Tue Jul 12, 2016 03:00PM
This handout image provided by UNMISS, the United Nations Mission in South Sudan, on July 11, 2016, shows some displaced women, men and children taking shelter at the UN compound in Tomping area in Juba. (AFP photo)
This handout image provided by UNMISS, the United Nations Mission in South Sudan, on July 11, 2016, shows some displaced women, men and children taking shelter at the UN compound in Tomping area in Juba. (AFP photo)

At least 36,000 people have been displaced since fresh heavy fighting erupted in South Sudan's capital, Juba, on July 8, the UN says.

Vanessa Huguenin, spokeswoman for the Office for the Coordination of Humanitarian Affairs (OCHA) said on Tuesday that the number was likely to "evolve" in light of the volatile situation.

"The latest fighting since Friday has displaced 36,000 people," Huguenin said, referring to clashes between troops loyal to President Salva Kiir and rebels backing his opponent First Vice President Riek Machar.

The UN humanitarian agency earlier said in a statement that the displaced had sought shelter in sites run by the UN mission in South Sudan, known as UNMISS, and other locations across the volatile city.

The "recent fighting has had a devastating impact on the civilian population," the statement said, adding that "most of the affected people are women and children."

"Access to those in need is limited by the ongoing fighting and insecurity," the OCHA warned. "It is imperative that civilians are allowed to move freely to places of refuge, and that humanitarian staff and their assets are protected to allow immediate, safe and unhindered access to those in need."

The UN agency said heavy rains in parts of Juba had worsened the situation.

A fragile ceasefire called by both President Kiir and Machar appeared to be holding in Juba on Tuesday.

Machar on Monday called for a ceasefire shortly after a similar call by the president to halt days of deadly fighting between their forces.

The ceasefire initially announced by President Kiir came into effect on Monday.

Kiir said he will remain committed to the 2015 peace agreement he signed in August of that year with rebels. 

South Sudanese government's attack helicopters hover over the Checkpoint district of the capital, Juba, near the Jebel district which has seen some of the heaviest fighting, July 11, 2016. (AFP photo)

Thousands of people have been killed and more than three million forced to flee their homes in the conflict that started in December 2013, when President Kiir sacked Machar, his former deputy, only two years after the country seceded from Sudan.

The two sides eventually signed an agreement in August last year to bring the conflict to an end. As part of the deal, Machar returned to Juba in April to take up the post of the first vice president in a national unity government.

Despite the August 2015 peace deal, battles persist across the country. There are numerous militia forces that do not abide by peace agreements and are driven by local agendas.