Egypt has reopened its Rafah border crossing with Gaza, allowing people to cross freely for the first time in four years.

However, men aged between 18 and 40 will still require a permit.

Egypt imposed the blockade with the co-operation of Israel after the militant group Hamas took control of Gaza in 2007.

Israel said it is 'worried' by the decision to reopen the crossing, which it says will facilitate arms smuggling to Hamas.

Home Front Defence Minister Matan Vilnai told public radio it would create 'a very problematic situation'.

The United Nations had called the blockade illegal and repeatedly demanded it be lifted.

Hamas spokesman Fawzi Barhum has said the move was 'a courageous and responsible decision which falls in line with Palestinian and Egyptian public opinion'.

'We hope that it is a step towards the complete lifting of the siege on Gaza,' he said.

The European Union also praised the move and said it was in consultations with Egypt, the Palestinians and Israel about returning its team of advisers to monitor activity along the frontier.

Sinn Féin Foreign Affairs Spokesperson Pádraig Mac Lochlainn welcomed the reopening of the border crossing, saying the blockade of Gaza is an 'outrageous denial of human rights'.