Figures show little let-up in numbers joining Islamic State despite bombing of IS strongholds and crackdown by authorities within France.
One of the teenagers returned home after police alert but French officials fear the other 'radicalised' girl could be trying to head for Syria.
Women now make up more than a third of French citizens travelling to Iraq and Syria to join IS, up from just 10 percent in 2010.
Charaffe el Mouadan was said to be a 'direct link' to Abdelhamid Abaaoud, the Paris attacks cell leader, according to US military official.
Call to detect false Syrian passports comes after two of the suicide bombers in the Paris attacks were found to be carrying such documents.
The French president met with personnel aboard the French navy flagship, the spearhead for French airstrikes on Islamic State group in Syria.
As MPs debate joining attacks on Islamic State group in Syria, France regards a 'yes' vote as being of high military and diplomatic importance.
Official at the Paris prosecutor's office said the two men, aged 19 and 20, were arrested near Tunisia's southern border with Libya.
French president makes unusual intervention urging Britain's House of Commons to back PM's request for Britain to join military coalition.
French foreign minister said that winning back Islamic State 'capital' Raqqa was priority and could involve help from Syria regime troops.
After Moscow meeting, President Hollande said he and Vladimir Putin agreed to 'increase information and intelligence exchange, intensify airstrikes'.
French president will meet Russian leader Vladimir Putin as part of push for international cooperation against Islamic State following Paris attacks.
In the wake of the Paris terror attacks, President François Hollande has carried out a 180 degree U-turn on French policy towards the Syria crisis. Previously the French stance was that neither Islamic State nor current leader Bashar al-Asad was acceptable in Syria. Now the approach is an all-out focus on destroying IS. On Thursday November 26th, Hollande will meet Assad's ally, Russian leader Vladimir Putin, in Moscow to help build an alliance to destroy the organisation. But, Thomas Cantaloube argues, apart from air strikes, there seems little real strategy to restore peace to Syria and find a political solution.
Two raids against IS targets in Syria and Iraq were launched from the Charles de Gaulle which arrived in the eastern Mediterranean on Monday.
Manuel Valls said the EU needed to 'take responsibility' over border controls or cherished passport-free Schengen zone would be in danger.