US Secretary of State Antony Blinken has spoken with Sudan’s army chief General Abdel Fattah al-Burhan and Rapid Support Forces paramilitary group commander Mohamed Hamdan Dagalo, according to a statement.

Blinken said that he welcomes the announcement of a three-day Eid Al-Fitr ceasefire.

US citizens in Sudan should have no expectation of a US-government coordinated evacuation from the country, deputy State Department spokesperson Vedant Patel has said, amid heavy firing heard in the capital Khartoum.

Patel told reporters at a press briefing that given the closure of Khartoum’s airport and the uncertain security situation in the country, citizens there should make their own arrangements to stay safe.

Heavy firing has continued in Sudan’s capital Khartoum after the army declared a three-day truce, and the source of the firing was unclear, according to witness speaking to Reuters news agency.

There were also air strikes heard from time to time, the Reuters witness added.

Sudan’s army has said it agreed to a three-day truce starting to enable the Sudanese people to celebrate the Muslim festival of Eid al-Fitr ending the holy month of Ramadan.

“The armed forces hope that the rebels will abide by all the requirements of the truce and stop any military moves that would obstruct it,” the army said in a statement.

Earlier on Friday the paramilitary Rapid Support Forces (RSF), which has been battling the army across Sudan for nearly a week, agreed to the 72-hour truce.

No decision has been made to evacuate US diplomatic personnel from Sudan but the United States is preparing for such an eventuality if it becomes necessary, the White House has said.

John Kirby, the White House national security spokesperson, said all US citizens in Sudan must “make their own arrangements to stay safe” as violence rocks the country.

He said President Joe Biden had approved a plan earlier this week to move US forces nearby in case they are needed to help evacuate US diplomats.

“We are simply pre-positioning some additional capabilities nearby in case that they’re needed. But I want to stress again … there’s been no decision to move forward with any kind of an evacuation at this time,” Kirby told reporters.

Paul Dillon of the International Organization of Migration says fighting between the warring sides in Sudan has intensified in El-Obeid, where an IOM employee was killed earlier on Friday.

“Our staff member, his wife and their newborn child got into a private vehicle and headed south to relocate to a safer place,” Dillon told Al Jazeera from Geneva.

“About 50km outside of El-Obeid, they found themselves in crossfire between two factions,” he said.

“Our staff member was critically injured but he managed to drive the car some distance away to a health clinic. Unfortunately, he died of his injuries,” Dillon added.

The US military is preparing as many options as possible before a possible evacuation from the US embassy in Sudan but no decisions have been made, according to US Defense Secretary Lloyd Austin.

“We’ve deployed some forces into theatre to ensure that we provide as many options as possible if we are called on to do something. And we haven’t been called on to do anything yet,” Austin told a news conference at Ramstein Air Base in Germany. “No decision on anything has been made.”

Switzerland says it will examine ways to evacuate Swiss nationals from Sudan and a portion of its embassy staff during fighting between the army and a paramilitary force.

The Department of Foreign Affairs said about 100 Swiss nationals are registered in Sudan while others are thought to be visiting the Red Sea area as tourists.

Bern is liaising with other countries for a possible joint evacuation but stressed that a series of conditions would have to be met, including guarantees of safe airspace.

Sweden will evacuate its embassy staff and their families from Sudan as soon as the situation makes that possible, Prime Minister Ulf Kristersson has said, adding that Sweden was coordinating its policy with other countries.

“The decisions we have taken mean that, it will be possible to evacuate … embassy personnel and their relatives if and when the security situation allows,” Kristersson told reporters.