New York legislators move to strip Gov. Andrew Cuomo of pandemic powers. Cuba nears final testing for its first vaccine. Japan begins inoculations, with the Olympics on the horizon. As lawmakers push for billions of dollars to fund the nation’s efforts to track coronavirus variants, the Biden administration announced on Wednesday a new effort to ramp up this work, pledging nearly $200 million to better identify the emerging threats. Calling it a “down payment,” the White House said that the investment would result in a significant increase in the number of positive virus samples that labs could sequence. Public health laboratories, universities and programs run by the Centers for Disease Control and Prevention sequenced more than 9,000 genomes last week, according to the database GISAID. The agency hopes to increase its own contribution to 25,000 genomes a week. “When we will get to 25,000 depends on the resources that we have at our fingertips and how quickly we can mobilize our partners,” Dr. Rochelle Walensky, the C.D.C. director, said at a White House news conference on Wednesday. “I don’t think this is going to be a light switch. I think it’s going to be a dial.” The program is the administration’s most significant effort to date to address the looming danger of more contagious variants of the virus. A concerning variant first identified in Britain has infected at least 1,277 people in 42 states, although scientists suspect the true number is vastly higher. Doubling about every 10 days, the B.1.1.7 variant that emerged in Britain threatens to slow or reverse the rapid drop of new coronavirus cases. From a peak of almost 260,000 new cases a day, the seven-day average daily rate has fallen to below 82,000, still well above the high point of last summer’s surge, according to a New York Times database. What’s more, Dr. Walensky said that the nation had seen its first case of B.1.1.7 that had gained a particularly worrying mutation that has been shown in South Africa to blunt the effectiveness of vaccines. Other worrisome variants have also cropped up in the United States, including one that was first found in South Africa and weakens vaccines. The F.D.A. is preparing for a potential redesign of vaccines to better protect against the new variants, but those efforts will take months. In the short term, experts say, it is critical to increase sequencing efforts, which are too small and uncoordinated to adequately track where variants are spreading, and how quickly. Scientists welcomed the new plans from the Biden administration. “It’s a huge step in the right direction,” said Bronwyn MacInnis, a geneticist at the Broad Institute. Dr. MacInnis said that the “minimal gold standard” would be sequencing 5 percent of virus samples. If cases continue to fall, then 25,000 genomes a week would put the country near that threshold, she said, which is “where we need to be to be detecting not only known threats, but emerging threats.” Trevor Bedford, an evolutionary biologist at the Fred Hutchinson Cancer Research Center, said there had been “substantial gains” in national sequencing efforts since December. Still, he said that the C.D.C. would also need to make improvements in gathering data about the genomes — such as tying it to information from contact tracing — and then supporting the large-scale analysis on computers required to quickly make sense of it all. “There’s too much of a focus on the raw count that we’re sequencing, rather than turnaround time,” he said. White House officials cast the sequencing ramp-up as part of a broader effort to test more Americans for the virus. The Department of Health and Human Services and the Defense Department on Wednesday announced substantial new investments in testing, including $650 million for elementary and middle schools and “underserved congregate settings,” like homeless shelters. The two departments are also investing $815 million to speed the manufacturing of testing supplies. The C.D.C.’s $200 million sequencing investment is dwarfed by a program proposed by some lawmakers as part of an economic relief package that Democratic congressional leaders aim to pass before mid-March. Senator Tammy Baldwin, Democrat of Wisconsin, introduced legislation to enhance its sequencing efforts. House lawmakers have allocated $1.75 billion to the effort.