Egypt's President Hosni Mubarak has stepped into a row with Algeria, vowing he will not tolerate the "humiliation" of Egyptian nationals abroad.
The dispute was triggered by violence following football World Cup qualifying matches between the two north African Arab nations.
Algeria won the crucial play-off, but each side has accused the other's fans of attacking their supporters.
The governing body of world football, Fifa, is investigating the violence.
Media in Cairo says in a country where political demonstrations are usually heavily suppressed this is an unusual site and a further sign of how strained Egypt's relationship with Algeria has now become.
In the televised statement to a joint session of parliament, President Mubarak said his country will not be lax in defending the rights and integrity of its citizens.
"Egypt does not tolerate those who hurt the dignity of its sons," he said.
Although he did not mention Algeria by name, our correspondent says it was clear he was referring to the row that has occurred following violence that spilled over following the matches on 14 and 18 November.
Mubarak said: "We don't want to be drawn into impulsive reactions. I am agitated too, but I restrain myself."
Algeria has demanded that Egypt stop what it describes as "a media campaign" against it following the violence.
On Friday, riot police had to quell a violent demonstration near the Algerian embassy in Cairo. Egypt's interior ministry said 35 people were injured.
A day earlier, around 1,000 Egyptians burned Algerian flags in a street near the Algerian embassy. Algeria beat Egypt 1-0 in a play-off in Sudan on Wednesday.