Denmark has placed advertisements in four Lebanese newspapers announcing tighter regulations and cuts in provisions for asylum seekers.

The advertisement published on Monday said that social assistance for newly arrived refugees was being reduced by up to 50 percent.

Those granted temporary protection would not have the right to family reunification for the first year of their residence, the ad warned.

New refugees will have to be able to speak and understand Danish in order to obtain a permanent residency.

Denmark trying to scare off would-be migrants with these ads in #Lebanon media: pic.twitter.com/8uQasJJBF6 — Sara Hussein (@sarahussein) September 7, 2015

"There will be a special return centre for rejected asylum seekers to ensure [they] ... leave Denmark as quickly as possible," the advertisement added.

The new measures went into effect on Tuesday.

Lebanon hosts 1.1 million Syrians who have fled the four-year-long conflict that has devastated their homeland.

Syrians are also the largest nationality among those trying to reach northern Europe via sea crossings to Greece followed by an arduous overland route through the Balkans and Hungary.

Most of the refugees and migrants are seeking to reach Germany and Sweden, which are known for their openness to asylum claims from Syrians.

Almost half of the claims for asylum lodged by Syrians in European countries have been made in those two countries, with another third lodged in countries along the Balkan route or in the Netherlands, according to UN refugee agency UNHCR.

A total of 348,540 Syrians had lodged asylum claims in Europe by July 2015, according to UNHCR, while more than 4 million are hosted in Turkey, Lebanon, Jordan and Egypt.

Another 7.6 million Syrians are displaced internally, meaning that more than half the country's pre-war population of 22.4 million has been driven from their homes by the conflict.