PARIS — Echoing a warning by Britain, France threatened Thursday to deliver weapons to Syrian rebel groups on its own if the European Union refuses to lift an arms embargo on the embattled Middle Eastern nation.
The warning, from Foreign Minister Laurent Fabius, seemed designed to pressure the 27-nation European Union to change its policy, which bars arms deliveries to either side in the two-year-old civil war pitting President Bashar Assad against a broad-based rebel movement ranging from army deserters to Islamist extremists.
‘‘We cannot accept that there is a current lack of balance, with on one side Iran and Russia delivering arms to Bashar and on the other rebels who cannot defend themselves,’’ Fabius said during a France-Info radio interview. ‘‘Lifting the embargo is one of the only ways that remain to change the situation politically.’’
The United Nations said the number of registered Syrian refugees jumped 10 percent in the past week alone, part of what the UN commissioner for refugees called a ‘‘staggering escalation.’’
Last week, the United Nations said the number of registered refugees in Jordan, Lebanon, Turkey, Egypt, Iraq, and North Africa had reached 1 million. On Thursday, Reem Alsalem of the UN refugee agency said more than 121,000 refugees registered since then, the Associated Press reported.
The Syrian rebel command repeatedly has asked for more advanced weapons in the fight against Assad’s army. It has singled out a need for portable ground-to-air missiles to defend against Syrian jet fighters and helicopter gunships and antitank missiles to fight the T-72 tanks, whose artillery is a potent weapon against lightly armed insurgents.
The various rebel organizations so far have bought weapons with money and logistical help provided mainly by Saudi Arabia and Qatar. The Obama administration, although calling for Assad to step down, so far has refused to help arm the rebels, arguing that any weapons provided could end up in the hands of radical jihadists.
Rebel weapons purchases so far have been limited primarily to light arms, such as assault rifles. Recent reports from Syria, however, indicate that some rebel units have obtained antitank missiles.
The German news magazine Der Spiegel, quoting participants, reported this week that US trainers are showing rebels how to use the antitank weapons at a camp in Jordan. It was unclear, the magazine said, whether the trainers were US soldiers or contract personnel.
Fabius’s declaration on Thursday followed a warning issued Tuesday by British Prime Minister David Cameron. Responding to questions from reporters, Cameron said London will abide by the EU embargo for now but reserves the right to supply arms independently if other European nations refuse to change their minds in the near future.
‘‘It is not impossible that we’ll proceed the way we see fit,’’ Cameron declared.
To hasten the EU decision, Fabius said, France has asked that the European bloc move up the date of a foreign ministers’ meeting that had been planned for the middle of May in Istanbul.
One purpose of the meeting would be to review the embargo, which the EU foreign ministers decided to maintain during a Feb. 17 meeting in Brussels.
The weapons question also is likely to arise at an EU summit Thursday and Friday in Brussels, although the foreign ministers’ gathering is the official forum for revisiting such a decision.
At the last meeting, Britain’s push for lifting the embargo was opposed mainly by northern European nations, including Sweden, Luxembourg, and Germany. Their argument was that supplying weapons to the rebels would only escalate the civil war without changing the course of the struggle, which already has killed an estimated 70,000 people.
Leaders of the northern European nations have given no sign that they have changed their minds. German Foreign Minister Guido Westerwelle told a German newspaper he wanted ‘‘to avoid a conflagration that could ignite the whole region.’’
As the fighting in Syria has intensified, growing numbers of Syrians have fled their country. UN officials said about 4 million of the country’s 22 million people have been forced from their homes by the fighting, including 2 million who remain in Syria.