EU seeks new rules on internal border checks

"Very soon we shall be in a position to present our proposals," he said.

One EU commission official noted that a possible option for the reform would be to allow the states to use terrorism, and not migration flows, as a basis for internal controls.

"It [terrorism] is really not explicit, it is really not covered by the rules," she said, noting the rules are vague in regard to such serious threats to internal security.

"We are still exploring options whether there is [a need to make terrorism explicit in the rules] but we have said that we recognise that is one of the grey areas of the border code."

A new legal basis, based explicitly on terrorism, could allow the same states to then continue the border controls after the November deadline and possibly without limits on the extensions.

The announcement comes ahead of a November deadline for Austria, Denmark, Germany, Sweden and non-EU member state Norway to lift their internal checks.

It also follows previous statements by Avramopoulos, who told reporters over the summer that the countries would no longer be able to prolong border controls for another six months.

All five over the summer had demanded the six-month extensions, as part of a wider effort to prevent migrants from moving north of Greece and elsewhere. Those controls must end in November, given that the code imposes a two-year limit on the six-month extensions, for reasons linked to migration movements.

"There are some countries that have presented justified reasons in order to ask for an extension of internal border controls, but this period is approaching its end and it is not legally justified to prolong it," Avramopoulos noted on Wednesday.

But intense pressure from Germany and France, along with other EU states, who want the rules reformed, appears to have eased the commission's position, as it is now preparing to launch a reform of the code.

Schengen states are currently only allowed to temporarily reintroduce controls at the internal borders when there is serious threat to public policy or internal security.