GENEVA, Nov. 9 (Xinhua) -- The UN refugee agency UNHCR said Friday that it expects all countries, including the United States, to protect any person in need of refugee assistance without obstruction.

The UNHCR issued a statement after the U.S. government said Thursday that immigrants who enter the country illegally would be banned from applying for asylum.

Among the people on the move in Central America and Mexico today, many are fleeing life-threatening violence or persecution and need international protection, said the refugee agency.

"UNHCR expects all countries, including the United States, to make sure any person in need of refugee protection and humanitarian assistance is able to receive both promptly and without obstruction in accordance with the 1967 refugee protocol to which the United States is a party," the statement said.

The U.S. move on Thursday is widely perceived as a measure targeting a caravan of immigrants from Central American countries moving toward the U.S.-Mexico border.

The refugee agency said that in an ideal and predictable world, asylum seekers should present themselves at the border and request protection.

"However, the reality of refugee flight is complex and requires management in a structured way with dignified reception arrangements," said UNHCR.

It noted that long-standing insufficient reception capacity at official U.S. southern border ports of entry is resulting in significant delays in northern Mexico and is forcing many vulnerable asylum-seekers to turn in desperation to smugglers and cross the border irregularly.

Many asylum-seeking families making this desperate choice are not trying to evade border authorities.

UNHCR said that national security and dignified reception of refugees and asylum-seekers are not mutually exclusive, but rather mutually reinforcing.

The UN refugee agency said it "stands ready at all times to support the United States and all governments and civil society partners working to guarantee that any person fleeing life-threatening violence or persecution is able to reach safe ground and is able to have their claim reviewed."