Francesco Malavolta, File, Associated Press
In this Saturday, Feb. 14, 2015 file photo, Migrants wait to disembark from an Italian Coast Guard ship after being rescued in Porto Empedocle, Sicily, southern Italy. Libya, virtually a failed state the past years, has provided a perfect opportunity for the Islamic State group to expand from its heartland of Syria and Iraq to establish a strategic stronghold close to European shores.

BRUSSELS — The European Union stands ready to beef up its border surveillance mission in the Mediterranean if Italy requests and is supplying 13.7 million euros ($15.6 million) to help Rome cope with the migrant influx, the EU's top migration official said Thursday.

"We are ready to respond constructively if Italy identifies the need to step up Operation Triton," Dimitris Avramopoulos said.

He also announced that the Triton mission operating in the Mediterranean Sea would be extended until at least the end of 2015.

The mission was launched in November as Italy deals with growing numbers of would-be migrants attempting the perilous crossing from Libya headed mostly for the southern island of Lampedusa.

Italy withdrew its search and rescue mission, Mare Nostrum, in December due to heavy costs and because it appeared to be a safety net that encouraged more migrants.

Some 19,500 migrants have been picked up in the Mediterranean since November, according to EU figures. Of those, 5,600 were rescued in January, a 50 percent increase over the same month in 2014.

More are expected as the weather improves.

In a new escalation on Sunday, four armed smugglers threatened an Italian Coast Guard motorboat involved in one of several operations that rescued more than 2,000 migrants.

Some Italian officials fear that terrorists, mingled among boatloads of migrants, could reach Italy.

"We cannot turn a blind eye, and we cannot carry on as if it was business as usual," said Avramopoulos.

One option tried in Greece in 2010-2011 but not explored with Italy is the use of rapid reaction teams from the EU borders agency Frontex.

They could be deployed with seven days if any formal request is made, said an EU official who is an expert on Frontex but is not permitted to speak publicly about the agency's work.

"There is a pool of 1,800 persons that are being trained nearly constantly," he said. The official confirmed that the use of force is permitted if Italy requests it.

Triton, meant to operate for only a few months, has just three aircraft and nine ships at its disposal, most of which cannot work in open seas.

In Rome, Italian Foreign Minister Paolo Gentiloni he hopes further assistance will be agreed in Brussels on March 4 at an EU meeting on migration.

Nicole Winfield in Rome contributed to this report.