After Samsung pushed back the Galaxy S3 release date by a week in Canada, it was believed that Galaxy S3's debut in U.S. may also face similar conditions. And now, the reports seems to be true as both Sprint and T-Mobile have confirmed that some users will face delays in shipment of Galaxy S3 due to the heavy demand for the smartphone in global market. On the other hand, AT&T hasn't announced any official release date yet, while Verizon Wireless will be shipping the device next month.

Citing "overwhelming demand and limited supply" for Samsung Galaxy S3, Sprint announced on Tuesday that the carrier is "little behind" on shipments of new Galaxy smartphone.

"The 16GB version of Samsung Galaxy S III device will be available in Web Sales and Telesales beginning on Thursday, June 21. It will be in all remaining sales channels next week. We are optimistic that we'll be shipping all Samsung Galaxy S III-16GB pre-orders this week and that they will be delivered by June 21 as anticipated. There is a chance, however, that we may be a day or two late. We anticipate shipping all Samsung Galaxy S III-32GB pre-orders next week," said Sprint on Tuesday.

According to folks at Tmo News, T-Mobile USA is also facing similar conditions. However, T-Mobile will be launching the smartphone on scheduled date but in selected markets only. The carrier will release Galaxy S3 in top 29 markets on June 21, while it will release in rest of the country on June 27.

The selected 29 markets to receive Samsung Galaxy S3 on June 21 are:

• Los Angeles, CA
• Chicago, IL
• Phoenix, AZ
• Houston, TX
• San Diego, CA
• New York, NY
• Seattle, WA
• Miami/Ft. Lauderdale, FL
• Dallas/Ft. Worth, TX
• San Francisco, CA
• Salt Lake City, UT
• Denver, CO
• Minneapolis, MN
• Tampa/St. Petersburg, FL
• Philadelphia, PA
• San Antonio, TX
• Portland, OR
• Austin, TX
• Atlanta, GA
• Kansas City, MO
• Boston, MA
• Sacramento, CA
• Orlando, FL
• Detroit, MI
• Washington DC
• Cleveland, OH
• Jacksonville, FL
• Charlotte, NC
• McAllen, TX