Thailand and Cambodia have agreed “to cease all shooting” effective Friday, according to United States President Donald Trump.

Trump announced the agreement to restart the ceasefire in a social media post following calls with Thai Prime Minister Anutin Charnvirakul and Cambodian Prime Minister Hun Manet on Friday.

“They have agreed to CEASE all shooting effective this evening, and go back to the original Peace Accord made with me, and them, with the help of the Great Prime Minister of Malaysia, Anwar Ibrahim,” Trump wrote on his Truth Social platform.

Fighting between the Southeast Asian neighbours this week has killed at least 20 people and displaced about half a million on both sides of the disputed border.

The original ceasefire between the two nations in July was brokered by Malaysia and pushed through by pressure from Trump, who threatened to withhold trade privileges unless Thailand and Cambodia agreed.

It was formalised in more detail in October at a regional meeting in Malaysia that Trump attended.

However, Thailand suspended the agreement in November after Thai soldiers were wounded by landmines at the border.

Both sides have continued a propaganda war, repeatedly blaming the other for reigniting a long-running conflict over the colonial-era demarcation of their 800-kilometre (500-mile) border.

The latest flare-up in violence began when a Thai engineering team was allegedly fired on by Cambodian troops.

The fighting entered its fifth day on Friday, with Thailand upping air strikes in recent days.

Neither Thailand nor Cambodia have independently confirmed the latest deal.

However, earlier in the day, Prime Minister Anutin Charnvirakul said he told Trump that the onus was on Cambodia to end the violence.

Anutin said Trump had voiced his support for a ceasefire during a call.

“I replied that he’d better tell that to our friend,” Anutin added, referring to Cambodia.

“It needs to be announced to the world that Cambodia is going to comply with the ceasefire.”

Reporting from Washington, DC, on Friday, Al Jazeera’s Kimberly Halkett said Trump appeared to be using the announcement to again burnish his self-styled image as a global “peacemaker”.

“The US president has invested himself personally in all of this. And as a result, he really is keen to see this truce that was brokered in July resume,” Halkett said.

“He keeps repeatedly saying, ‘I’ve solved eight wars’. He is desperate to position himself and to position his legacy as being one of a peacemaker and a global deal maker, and the fact that this unravelled so quickly, obviously eroded that,” she added.

The roots of the Thai-Cambodian border conflict lie in a history of enmity over competing territorial claims stemming from a 1907 map created while Cambodia was under French colonial rule, which Thailand maintains is inaccurate.

Tensions were exacerbated by a 1962 International Court of Justice ruling that awarded sovereignty to Cambodia, which still riles many Thais.