Refugees International has urged US President Donald Trump to impose financial sanctions and arms embargo on Myanmar who is accused of ethnic cleansing and crimes against humanity.

"During his UN address, President Trump must demand strong measures to end the ethnic cleansing and crimes against humanity being perpetrated by the Myanmar military against the Rohingya people," said Refugee International President Eric Schwartz at a press conference at a city hotel in Dhaka today.

The Washington-based organisation, working on refugees and migrants, said the US should prohibit military to military cooperation with Myanmar until abuses are ended and individuals involved in planning, aiding or carrying out such abuses against the Rohingyas are held accountable.

The statement comes when more than 400,000 Rohingyas fled to Bangladesh following the military crackdown against them since August 25. Myanmar says it is a response to the Rohingya insurgents' attacks on Myanmar police posts and an army base.

Refugees International President Eric P Schwartz and Senior Advocate for Human Rights Daniel P Sullivan visited Cox's Bazar and collected first hand information on the recent arrivals of the Rohingya men and women.

"There is no doubt in my mind that Burma is responsible for crimes against humanity," said Schwartz. This is creating a huge influx to Bangladesh that is under pressure of resources, he added.

"We urge President Trump to offer strong words of support for the efforts of Bangladesh to provide refuge for the Rohingya," Schwartz said.

He also demanded that Donald Trump urge governments of the world to rally to provide financial support for the humanitarian response in Bangladesh.

Asked if the appeals for aid to the world community have been receiving enough response, Schwartz said, "not yet". "We hope that the appeals will be fully met."