The Trump administration’s decision to delay federal funding to convert Caltrain from diesel to electric power is already having a ripple effect in San Francisco.

The San Francisco Board of Supervisors, acting as the city’s Transportation Authority, was scheduled to vote this week on whether to allocate as much as $6.7 million in sales tax money for preliminary engineering work to bring high-speed trains into the new downtown Transbay Transit Center.

But without an electrified Caltrain line, there can be no high-speed trains into downtown San Francisco. “Why are we spending money to design something that may never be built at all?” said Supervisor Aaron Peskin, who chairs the authority’s board.

Some officials hold out hope that President Trump will eventually release the $647 million in electrification funding for Caltrain, but that’s hardly a sure thing.

Peskin figured it was time to hold off, at least until the authority hears more next month from city transportation planners. So on Friday, the authority sent word that the city’s money, like the federal contribution, will stay on ice.

S an Francisco Chronicle columnists Phillip Matier and Andrew Ross appear Sundays, Mondays and Wednesdays. Matier can be seen on the KPIX TV morning and evening news. He can also be heard on KCBS radio Monday through Friday at 7:50 a.m. and 5:50 p.m. Got a tip? Call (415) 777-8815, or email matierandross@ sfchronicle.com. Twitter: @matierandross