By Subir Bhaumik BBC News, Calcutta
Ms Ellen has just visited Nepal and BhutanBhutanese refugees living in Nepal are facing "severe intimidation" ever since plans to resettle them in the West were announced, a senior US official says.
US Assistant Secretary of State for Population, Refugees and Migration, Ellen Sauerbrey, says the refugee leaders in the camps are to blame.
Nepal is home to about 107,000 ethnic Nepalese expelled from Bhutan, which says they are illegal immigrants.
The US has said it will take 60,000 refugees, but says it can take more.
"There is no question that severe intimidation began in the camps when the US made the offer of resettlement," Ms Sauerbrey told the BBC.
She was stopping over in the city of Calcutta on way to Delhi after a tour of Nepal and Bhutan.
Ms Sauerbrey blamed the refugee leaders in the camps in Nepal for the "intimidation".
"For those who have spent 17 years trying to develop a programme to return to Bhutan, the idea that a large number of the refugees will come to the US reduces their political power," she said.
"The refugees have also been fed on false rumours consistently."
Leaders of these Bhutanese refugees have been trying to organise them for a long march back home through India.
But Delhi - which has very friendly relations with Thimphu - has deployed border guards and police to foil these marches.
The refugees have been living in Nepal since the 1990s
Ms Sauerbrey says the government of Nepal must provide "adequate security" in the refugee camps, so that the UNHCR can provide resettlement information to the refugees and enlist those who voluntarily come forward to accept the offer.
"If there's enough security in the camps, I am confident most of these refugees would take up the offer of resettlement in the US," Ms Sauerbrey said.
She said the US was interested in resettling 60,000 of the refugees over five years, but there was no limit and no quota to the US offer.
"If more than 60,000 people are interested in being resettled and are referred to our programme by UNHCR, we will take those who qualify.
"Most will qualify unless someone has a record of violence in the camp," she said.
"We do not take these people because they are highly skilled or educated, we will take them for humanitarian considerations."
Ms Sauerbrey, who visited Kathmandu and the refugee camps in eastern Nepal before travelling to Bhutan, said the process was formally launched after Nepalese officials went to the camps with her delegation and announced publicly the Nepalese government's support of the resettlement programmes.
She said 3,000 refugees have already applied informally for resettlement in the US.
"Our goal this year is to interview about 15,000 and, in the next few years, we are expecting 20,000 to 25,000 per year, based on the interest generated amongst the refugees ," she added.
Bhutan says the refugees in Nepal are illegal immigrants
Ms Sauerbrey said the US government was keen to resolve the protracted refugee situation on humanitarian grounds.
"If you have been to refugee camps, they are not nice places and these people have been in the camps for 17 years. That is a long, long time," she said.
Ms Sauerbrey said the resettlement could resolve a major part of the problem but there were people in the camps who were genuinely Bhutanese citizens and would very much like to come home.
"The US and many other international communities do believe that Bhutan has a moral obligation with people who are genuinely Bhutanese citizens, to let them come home," she said.
Tens of thousand of Bhutanese of Nepali origin started fleeing the kingdom in the 1990s, complaining of persecution by the royal administration.
They found refuge in the camps in eastern Nepal, run by the UNHCR.
Several rounds of talks between Nepal and Bhutan have failed to resolve the issue.
But as Bhutan heads for its first national elections next year, the refugee leaders are pressing for the return of their people to the kingdom so that they can vote and regain their citizenship .