President Barack Obama heads to a North American leaders summit Wednesday, but may find slightly less chumminess than usual at "three amigos" talks between Canada, Mexico and the United States.
Obama travels to the ornate palace of Toluca, Mexico to meet President Enrique Pena Nieto and Prime Minister Stephen Harper of Canada.
The three nations, massive trading partners, are locked in several thorny disputes likely to surface in the talks and in a joint press conference later on.
Obama will no doubt face a new entreaty from Harper to quickly make up his mind on the Keystone XL pipeline project, which would carry crude from the oil sands in Alberta, across the continental United States to Texas.
Canada is deeply frustrated at delays in the project, which is awaiting a construction permit and has caught Obama's administration between its backers in the environmental community and claims it will create thousands of jobs.
But Harper is unlikely to get an answer, as Secretary of State John Kerry continues his deliberations on whether to give the project the go-ahead.
"What President Obama will do is explain to (Harper) where we are in the review ... and indicate that we'll of course let our Canadian friends know when we've arrived at a decision," said a senior US official on condition of anonymity.
"We would fully expect that Canada would continue to express its desire to see the process resolved, but it will run its course."
A State Department report earlier this month concluded that the pipeline would not significantly impact global warming, as Canada would extract the dirty tar sands oil even if it is not built.
Pena Nieto will meanwhile likely offer Obama some support, but also a measure of frustration over the failure to pass comprehensive immigration reform in the United States.
The US president made the issue a centerpiece of his agenda but has seen his hopes of enacting a law to bring more than 11 million illegal immigrants, many of them of Mexican origin, out of the shadows, repeatedly frustrated by Republicans in Washington.
Pena Nieto's government has also been investigating claims sourced to documents leaked by fugitive US contractor Edward Snowden that US National Security Agency (NSA) eavesdropping programs targeted his communications and those of two previous Mexican presidents.
Mexico and Canada are both prospective partners in the 12-nation Trans Pacific Partnership (TPP) trade pact that Washington is hoping to conclude this year.
But they will be keen to know how Obama plans to overcome opposition from fellow Democrats to the deal in a mid-term election year, as well as his hopes of securing "fast-track" powers to swiftly conclude the deal.
Despite the niggling frictions, US officials are in no doubt of the value of close relations with America's neighbors to the North and South.
A third of US exports go to the two countries and the trade supports 14 million jobs on US soil, US officials say.
As well as the TPP, US officials say they are also keen to talk about border security cooperation with Mexico and wider relations with nations in Latin America and the Caribbean.
But while there is plenty of business to be conducted in Mexico, there will be little time for pleasantries.
Obama will leave Washington early on Wednesday morning and return to the United States after the press conference with his fellow leaders, without stopping overnight in Mexico.