The identities of the two men have not been publicly released but they have both been charged, Belgium's federal prosecutor said this morning. Five other people were detained but later released.
Hollande also announced today that a bill will be presented to Parliament on Wednesday, proposing an extension of the country's state of emergency for three more months.
"France is at war," he said in his address in front of both houses of Parliament in Versailles, going on to specify that said war is with jihadist terrorism.
"Our democracy has triumphed over enemies much stronger than these cowards," he said.
The arrests come after a police operation in Molenbeek, a suburb of Belgium, where officials had believed Paris attack suspect Salah Abdeslam was hiding in a building. The siege ended without his capture, the mayor of the town said today.
It had been believed he was inside the building after police surrounded it and negotiated with someone inside via bullhorn, according to a law enforcement source.
The town was discovered Saturday to be home to one of the dead Paris attackers, according to a Federal Prosecutor spokesman.
Two of seven people detained were with the key suspect, Abdeslam, in Friday's attacks, when they were stopped by police at the France-Belgium border after the assault. But the police let them go because there were no BOLOs (arrest warrants) for them. Authorities later seized their car in Belgium.
The other five people who were arrested in Molenbeek in connection with Friday's attacks have been released, a Belgium Federal Prosecutor spokesperson confirmed to ABC News. Among the five people is Mohamed Abdeslam, the brother of the key suspect.
Belgium’s Interior Minister said Sunday the situation in Molenbeek is out of control.
Belgian Prime Minister Charles Michel said Molenbeek was a "giant problem," according to Belgian TV Sunday, and the government should "focus more on repression."
More than 500 Belgian nationals have left to fight in Syria, according to a Belgian database. Belgium has provided the most foreign fighters in Syria, per capita, of any European country.
A new sign of increased security measures in the region came today as American military personnel have been banned by the U.S. European Command from all unofficial travel to Paris, and any official travel needs to have permission from a general officer to proceed.
At least 129 people died in six coordinated attacks in Paris on Friday and 352 others were injured, 80 of whom remain in critical condition.
ABC News' Louise Dewast contributed to this report.