Germany's top security official Wednesday proposed introducing joint German-Polish patrols on the two countries' border to help clamp down on illegal crossings into Germany by migrants arriving from Belarus, but said no one has any intention of closing the frontier.

Authorities in Germany say about 4,500 such crossings have been registered since August. Many of them are people from Syria and Iraq who flew to Belarus in the hope of reaching the European Union via Poland.

Interior Minister Horst Seehofer said he has sent a letter to his Polish counterpart proposing joint patrols on the Polish side of the border to identify illegal crossings and arrest people smugglers. He said he hasn't yet received a reply.

Germany says it has offered assistance to Poland by seconding additional border guards and providing logistical support for housing migrants in the country.

Seehofer stopped short of introducing regular border checks on the border with fellow EU member Poland, something that authorities in the German border state of Brandenburg have opposed, or taking more drastic action.

“No one intends ... a closure of the border,” Seehofer told reporters after a Cabinet meeting in Berlin. That, he said, “would be legally very, very questionable at the moment, because the Poles for their part have taken very, very strong initiatives to prevent irregular immigration.”

“You won't find anyone in the interior ministry who has seriously suggested this in recent days and weeks,” Seehofer added.

Migrants are apparently being transported across Poland to the German border in trucks and cars. On Tuesday, a delivery truck with nearly 20 migrants crashed in western Poland.

While Germany and other EU countries have backed Poland's efforts to protect its border with Belarus, Berlin has also raised concerns about the humanitarian situation of migrants picked up at the Poland-Belarus border.

On Monday, EU foreign ministers looked at ways to stem illegal migration into the 27-nation bloc from Belarus, including stopping companies from leasing jets to Belarusian airline Belavia.

The EU has accused the government of Belarusian President Alexander Lukashenko of facilitating migration into the bloc in retaliation for EU sanctions. Thousands of migrants have been lured to Belarus on tourist visas and encouraged to cross into Poland, Lithuania and to a lesser extent Latvia – all three of which are EU nations that border Belarus.