BRUSSELS - A proposal to give the EU's executive the power to send forces unbidden into member states to defend the common European frontier will face resistance from some countries when it is published this week.

The European Commission wants to be able to deploy personnel from a new European Border and Coastguard Agency without, as currently required, the consent of the state concerned, EU officials told Reuters in early December, reflecting frustration with Greek reluctance to seek help with migrants.

European Union officials call it a largely theoretical "nuclear option" and stress that any infringement of national sovereignty would be balanced by the power of a majority of member states to block Commission intervention - similar to checks agreed during the euro debt crisis.

The Commission will set out the plan on Tuesday to reinforce its Frontex agency with up to six times more staff, EU officials said, following a commitment to an EU border guard in September by President Jean-Claude Juncker.

"We think the current situation justifies a certain ambition," the Commission's chief spokesman said on Friday, expressing confidence about backing from member states.

Failure to strengthen the external borders, senior officials argue, will see more states reimpose frontier controls inside the bloc, wrecking its cherished free movement area, and foster the rise of anti-EU nationalists like France's National Front.

But while big powers France and Germany support such EU power, other EU leaders may voice concerns at a summit on Thursday. Italy has pushed for a "Europeanisation" of external frontiers to relieve the costs on itself and Greece of policing the Mediterranean. But the plan may go too far for many leaders.(Reuters)