The foreign affairs minister says Ireland must remain on alert against the threat of Islamic extremists.

Charlie Flanagan says he met the Justice Minister Frances Fitzgerald this morning to discuss intelligence, security and preventing similar attacks to those which killed 17 people in Paris last week.

Security experts say Ireland is being used as a hub by foreign jihadists travelling to Iraq and Syria to join ISIS.

In France, 10,000 members of the security forces are being mobilised to protect sensitive sites - a deployment which will begin on Tuesday.

French President Francois Hollande has held a crisis meeting with Cabinet ministers to discuss security measures after the attacks raised questions for the country's intelligence service.

Meanwhile scenarios similar to the attacks in Paris will be included in future counter-terrorism exercises by the British police and security services, Downing Street has said.

British Prime Minister David Cameron has met intelligence and security chiefs to discuss whether further measures are needed to deal with the threat of terror attacks in Britain.

Following the talks, a spokesman for Downing Street said it had been agreed that future exercises, which take place on a regular basis, should seek to learn from events in France.

Mr Flanagan says while we are not on the "frontline" there is a need for vigilance.