Earlier on Friday, while some Nehawu members demonstrated peacefully, other members tried to gain entry onto the University's campus where they were met by police who retaliated with teargas and stun grenades.
Some Nehawu members, however, managed to get through while others retreated and threw rocks and bricks at the police.
The university said they had broken through a fence to gain entry.
However, News24 saw protesters enter through an open gate where construction was taking place.
UP confirmed that there was only one instance where protesters tried to get onto the campus.
The clash between demonstrators and police was short-lived as the regional leadership quelled the situation and the other protesters re-joined those who were dancing and singing peacefully at the university's front gate.
During the initial clash, three demonstrators were arrested and have yet to be released despite negotiations between the union and the university to have them released.
No injuries were reported, but several protesters were affected by teargas.
Nehawu regional branch chairperson, Joseph Makhasa confirmed their demands.
Addressing the estimated 200 demonstrators outside of the university, the Nehawu leadership told their members they could go home and that their protest action had had a positive impact on negotiations.
They also said they would assemble at the university on Saturday morning to institute a university shutdown.
UP said classes continued as usual and that they would not permit any disruptions to the academic programme.
As per the negotiations, university spokesperson, Candice Jooste, said salary negotiations reached a deadlocked after the union refused the university's offer of a 7% general salary increase effective from March 1, 2017 as well as an additional R3 000 gratuity payment.
"The matter was then referred to the CCMA, which issued a certificate of non-resolution, which permits the union to embark on a protected strike," said Jooste.
"The university believes the offer is reasonable given the current economic conditions and that employees will be earning above the industry average. However, we will not compromise our own financial sustainability. The university respects workers' right to protest, and appeals to them to do so within the ambit of the law."