Serena Williams and Venus Williams

New York: Serena and Venus Williams have opted out of the United States' first-round Fed Cup tie against Germany in Hawaii this month.

New US captain Kathy Rinaldi announced her squad on Wednesday for the best-of-five match tie in Maui on February 11-12.

It doesn't include the Williams sisters, who met in the final of the Australian Open where Serena claimed her 23rd Grand slam singles title at the expense of her elder sister.

With the win, Serena regained the world number one ranking that had been held by Germany's Angelique Kerber, who had announced in January even before she launched her defence of her 2016 Australian Open title that she wouldn't make the trip to Hawaii.

The US team includes Australian Open singles semi-finalist CoCo Vandeweghe, Australian Open doubles champion Bethanie Mattek-Sands, Alison Riske and Shelby Rogers.

The German squad includes Laura Siegemund, Andrea Petkovic, Julia Goerges and Carina Witthoeft. The winners of the tie will face Spain or Czech Republic in the semi-finals of the women's nations tournament in April.3