U.N. official says plan to relocate 160,000 not enough. —

ATHENS, Greece — The United Nations’ top official for refugees said Monday that European Union plans to take in about 160,000 migrants are insufficient, and he urged Europe to provide asylum seekers with legal immigration options.

Antonio Guterres said the relocation program is a starting point but is not enough. Speaking in Athens, he called for the EU to accept more refugees and expand beyond Syrians, Iraqis and Eritreans.

His call came as authorities say asylum seekers in France are becoming bolder in attempts to challenge security forces and break through cordons preventing them from reaching Britain, and as Europeans deal with disruptions caused by border controls.

More than 500,000 migrants have entered Europe this year, four-fifths of whom paid to be smuggled by sea from Turkey to Greece.

Guterres, the U.N. high commissioner for refugees, said that “doesn’t make sense” when they could have a legal alternative. “We need to increase substantially the forms of people being able to come to Europe legally,” he said.

In Britain, hundreds of lawyers, retired judges and academics urged the government to take in more Syrian refugees, saying the offer of 20,000 is “too low, too slow and too narrow.”

In a letter published Monday, they said the United Kingdom’s offer is “deeply inadequate,” noting that in Lebanon — a country of 5 million — there are 1.2 million registered Syrian refugees.

The group said that even though the refugees have a right to legal protection, they are being driven “into the hands of people-smugglers.’”

The letter’s signees, many of whom have a human-rights background, said many members of the EU make it impossible for people to seek asylum via normal means of travel and that the entire system is dysfunctional.

Greek authorities said Monday that they rescued a total of 1,624 migrants who entered the country in dozens of boats from neighboring Turkey over the past three days.

The coast guard said the migrants were picked up at sea in 47 incidents near Greece’s eastern Aegean islands of Lesbos, Kos, Chios, Samos, Leros, Agathonissi and Farmakonissi.

In Calais, France, 200 migrants broke into the Eurotunnel’s French terminal over the weekend, clashing with police and prompting an hourslong suspension of the undersea rail service linking France and Britain. John Keefe, a Eurotunnel spokesman, said the “very aggressive and very organized” attempt represented “a different kind of tactic.”

“If they can’t get through on their preferred route without violence, will they then use violence to get through?” he said. “There has never been any anger before, but this was, ‘We don’t care. We are going through.’”