The trip could end with the US government paying back the entire cost of the trip.
The White House had originally claimed the US would receive a $1bn loan from the European Union to cover the costs of the train’s construction and maintenance.
But President Donald Trump’s team says that will not happen and instead will be paid back through a debt default and other financing measures.
Trump has previously suggested he could be willing to pay back the loan, but has since been more explicit in his public comments.
The president’s visit comes amid the threat of a major economic downturn in Europe.
According to an estimate by the Financial Times, the total cost of US goods imports from Europe could drop by at least a third, or possibly even more.
“The US has no interest in financing this trip, and the Treasury Department is not interested in financing it,” said one source familiar with the plans.
On Wednesday, Trump announced the cancellation of the Trans-Pacific Partnership trade deal.
EU leaders were expected to vote on the pact on Thursday, but that could change as the vote is postponed.
German Chancellor Angela Merkel and French President Emmanuel Macron will travel to Washington on Friday for a summit with Trump.
There are fears the US may be able to take advantage of the crisis in the eurozone to secure further aid from its largest trading partner.
US President Donald J Trump is scheduled to travel to Germany for talks with Chancellor Angela Trump and French president Emmanuel Macron on Thursday in an attempt to secure the approval of his planned $1.6trillion bond repayment to the European Central Bank.
European leaders are concerned about the economic impact of the US bond payment.
During the eurozone crisis, many European countries borrowed heavily to pay off their debt, and now Europe is in a similar situation, with many countries facing a debt burden of tens of billions of euros.
Last week, European Union leaders agreed to extend their bailout for a second time, with the aim of stabilising the eurozone and making sure the continent’s banks can recover.
A second round of eurozone-wide bailouts will be held on January 31.