Great Britain captain Anne Keothavong says the lack of top-20 players at the Billie Jean King Cup is "a tennis problem, not a player problem".

Only three of the world's top-20 will compete in this week's qualifying rounds, with Poland's Iga Swiatek and American trio Jessica Pegula, Coco Gauff and Madison Keys among those absent.

World number two Swiatek withdrew last week, saying she needed time to "focus on myself and my training".

Britain, meanwhile, are without Emma Raducanu, who has opted to train and "look after her body" after her Miami Open quarter-final run in her seventh event of the year.

The top teams in each round-robin group will advance to September's eight-team finals in Shenzhen, China.

"It's tough for every nation to put out their best players in each tie, Keothavong told BBC Sport in The Hague, where Britain are in a group with Germany and the Netherlands.

"The calendar is just makes it so difficult for players, so I'm empathetic as to how they are.

"The tennis circuit is brutal - you go from one week to the next and there's not much time to rest and recover.

"You have got to try and pick and choose your moments, but it's not a player problem - it's a tennis problem.

"One of these days maybe everyone can figure out a solution and work together."