(Adds quotes from Meirelles, background)
BUENOS AIRES, March 19 (Reuters) - Colombia proposed on Monday that the International Monetary Fund set up a pool of resources to assist several hundred thousand Venezuelan refugees who have fled an economic and political crisis, Brazil's Finance Minister Henrique Meirelles said.
The proposal was discussed at a meeting on the Venezuelan crisis by finance ministers, including U.S. Treasury Secretary Steven Mnuchin, on the sidelines of a G20 summit of major economic powers.
"The consensus is that the situation is extremely negative and we must by any means possible try to influence a solution to the problem and a change in Venezuela's situation, mainly from the humanitarian point of view," Meirelles told reporters.
The fund for Venezuelan refugees would be decided at the International Monetary Fund's meeting in April, he said. It would be for use solely outside Venezuela and not by socialist President Nicolas Maduro's "regime."
More than 500,000 Venezuelans have crossed into Colombia and 40,000 have left for Brazil as an economic meltdown worsened and opposition hopes of fair elections faded.
There are about 629,000 Venezuelan migrants in South America, up from around 84,000 in 2015, the International Organization for Migration said in December.
Colombia's government was preparing a statement on the proposal, a finance ministry official said in Bogota.
The countries concerned with the Venezuelan situation also discussed sanctions and debt repayment as ways to encourage a solution to the crisis, Meirelles said.
"Some countries are already applying sanctions, like the United States. In the case of Brazil, we are owed $1.3 billion in trade financing and want that repaid," he said. Venezuela recently paid arrears and is up to date, he added.
Other countries, led by Russia and China, favor a moratorium that would suspend Venezuela's payments, he said.
Besides the United States, Colombia and Brazil, Germany, Spain, Canada, Paraguay and summit host Argentina attended the private meeting. Russia and China did not attend.
Venezuela is undergoing a major economic crisis, with millions suffering food and medicine shortages, and Maduros government is late in paying about $1.9 billion in interest on its debt.
Moody's Investors Service downgraded Venezuela's sovereign rating further into junk territory on March 9, on an expectation that the continuing erosion of the country's payment capacity will lead to heavy losses to bondholders. (Reporting by Anthony Boadle Editing by Paul Simao)