BlackBerry (NASDAQ:BBRY), the beleaguered Canadian smartphone maker whose once solid market share has eroded to touchscreen offerings from competitors, announced that it has received its biggest customer order ever.

Without naming the buyer, BlackBerry said one of its “established partners” is buying 1 million BlackBerry 10s. The BlackBerry 10 is the new line of phones that the Waterloo, Ontario company rolled out in January.

Krista Seggewiss, a spokeswoman for BlackBerry, declined to say who the buyer was or define what the company meant by an “established partner.” BlackBerry works with corporate customers, government agencies and all the largest U.S. carriers. BlackBerry said the Z10, the new touchscreen smartphone, will be available to U.S. consumers with AT&T on March 22. It will be available for pre-order from Verizon starting today. The release will come several weeks after RIM launched the much-delayed devices elsewhere.

BlackBerry shares jumped 8.2 percent to $15.65 today in New York after the announcement. BlackBerry’s stock has climbed 32 percent this year.

CEO Thorsten Heins said previously he was disappointed the new BlackBerry would not be released in the United States until mid-March, but he said the U.S. and its phone carriers have a rigid testing system.

BlackBerry, formerly known as Research In Motion Ltd., announced the BB10 phones in January. The new phones run on a redesigned operating system and the company is pinning its comeback on the lineup. After pioneering the smartphone market, the company’s global share slipped to single digits amid competition from Apple’s iPhone and Google’s Android.

Heins told The Associated Press last month that the company would have to regain market share in the U.S. for BlackBerry to be successful. The U.S. has been one market in which RIM has been particularly hurt. The iPhone and phones running Google’s Android software now dominate. According to research firm IDC, shipments of BlackBerry phones plummeted from 46 percent of the U.S. market in 2008 to 2 percent in 2012.

For die-hard BlackBerry fans who covet a physical keyboard, Heins told the AP that a modern BlackBerry with a physical keyboard might not arrive in the U.S. until May or June, a month or two behind other parts of the world.

(Bloomberg News and The Associated Press contributed to this report)