Eritrea has accused Sudan of trying to assassinate President Isaias Afeworki and of government terrorism.
Sudan was plotting to kill President Isaias, Eritrea says
Meanwhile, Sudan's security chief, Saleh Gosh has accused Eritrea of wanting to topple the Sudanese government by supporting rebels.
Sudan's National Democratic Alliance opposition movement has its headquarters in Eritrea.
In recent years, relations between the countries have been strained and their border has been closed since 2002.
Eritrean Information Minister Ali Abdu Ahmed said Sudan "continues to step up its attempts to disrupt peace and stability in Eritrea and the region by pursuing its process of government terrorism an assassination attempts against the president".
But Mr Gosh said Eritrea was supporting Sudanese rebel groups which have set up bases in Eritrea.
Intelligence officials, he said, had seen camps belonging to the Darfur rebel groups in Asmara with the help of the Eritrean army.
"We believe the Eritrean army is involved in all these campaigns in the east," he told Reuters news agency.
Such comments are disseminated "for a diversion from domestic problems", Mr Ali Abdu said in his statement.
Large numbers of Eritreans live in Sudan and last month Sudan granted asylum to 60 Eritreans who arrived on a hijacked plane from Libya.