President Omar al-Bashir said on Sunday that the crisis in neighbouring Libya has impacted Sudan, with human traffickers using the East African country's territories to commit "cross-border crimes".
Speaking at a joint press conference with visiting UN-backed Libyan premier Fayez al-Sarraj, Bashir also said security issues in Libya had made Khartoum's fight against human trafficking "more expensive".
"We are affected directly by the insecurity in Libya, which has made it expensive for us to fight human trafficking, illegal immigration and cross-border crimes," Bashir said.
"Those who are committing these crimes are using the instability in Libya, and using Sudanese territories to commit their crimes."
Every year tens of thousands of illegal immigrants from the Horn of Africa cross Sudan and enter Libya for their onward journey to Europe across the Mediterranean.
In recent years European and African authorities have put pressure on Khartoum to boost efforts to curb illegal immigration and human trafficking.
Khartoum recognises the Tripoli-based Government of National Accord of Sarraj, a rival of Libyan military strongman Khalifa Haftar, who is accused by Sudan of enlisting rebels from the country's Darfur region to fight alongside his forces.
Bashir reiterated that accusation on Sunday.
"We have some Sudanese members of rebel groups active in Libya as mercenaries," he said, without elaborating.
Sarraj said the two leaders discussed the security situation in Libya.
"Sudan is of strategic importance to Libya, and we discussed how to secure the border," he said.
The two leaders did not talk about last month's closure of a Sudanese consulate and the expulsion of 12 diplomats by the Haftar-backed authorities in eastern Libya.
A pro-Haftar news agency had reported that the Sudanese mission in Kufra, an oasis in southern Libya, was closed on the grounds that it damaged "Libyan national security".
According to officials in Khartoum, dozens of young Sudanese -- both men and women -- have been killed in Libya fighting in the ranks of the Islamic State jihadist group.
Libya has been rocked by chaos since the 2011 fall and killing of longtime dictator Moamer Kadhafi in a NATO-backed revolution.
Jihadists, arms dealers and people traffickers have gained a foothold in the North African country as multiple authorities and dozens of militias vie for power.