(File Photo)

The US expressed alarm Wednesday over an increase in indiscriminate air and artillery strikes in Sudan, which have killed a large number of civilians.

"The United States is alarmed by the recent increase of indiscriminate air and artillery strikes in Sudan, including in Khartoum, South Darfur and South Kordofan states, which have resulted in high numbers of civilian casualties," State Department spokesman Matthew Miller said in a statement.

"We are particularly concerned with the reported Sudanese Armed Forces (SAF) September 10 airstrike in southern Khartoum that killed at least 43 people, the August 23 shelling exchange between the SAF and Rapid Support Forces (RSF) that killed at least 27 people – most of them women and children – in Nyala and continued shelling in a number of areas, including with the use of barrel bombs," he added.

Accusing both parties of instigating "unrelenting violence" which has caused death and destruction across Sudan, Miller said both parties "must comply with their obligations under international humanitarian law, including obligations related to the protection of civilians."

“The SAF and RSF each affirmed those responsibilities in the May 11 Jeddah Declaration of Commitment to Protect the Civilians of Sudan, and each has failed to live up to them in the months since," he said, noting that the US continues to support accountability for perpetrators of atrocities in Sudan.

"The warring parties must end this brutal conflict. The Sudanese people deserve freedom, peace and justice," Miller said.

At least 43 people were killed in an airstrike on a marketplace in the Sudanese capital, Khartoum, on Sunday, according to a medical group.

In a statement, Sudan's Doctors Syndicate said 55 people were also injured in the attack, which targeted an open market in the Mayo neighborhood in south Khartoum.

The attack came amid heavy fighting between the Sudanese army and the RSF paramilitary group in the capital.

For its part, the RSF accused the army of carrying out an airstrike in the Mayo neighborhood. But the Sudanese army denied the accusation, terming it as “misleading” and “false.”

More than 3,000 civilians have been killed and thousands injured in clashes between the army and the paramilitary group since April, according to local medics.

Several cease-fire agreements brokered by Saudi and US mediators have failed to end violence in the country.