England boss Gareth Southgate has warned his players not to expect automatic selection.

Manchester City fullback Kyle Walker was the most notable omission from Southgate's latest squad for the upcoming Euro2020 qualifiers against Bulgaria and Kosovo.

"That challenge is there for all of them, and whether they are younger or older, don't assume anything, because I think everyone has to keep performing if we're to challenge the best teams and that's how we are going to develop," Southgate said to reporters.

"They've got to play well and it's going to be harder to get in, because you can see the players we've had to leave out who've got a lot of caps between them, high-level players, we know there are some others around the fringes that could be close.

"And we know that there are some more young ones coming that are going to push that as well."

On 29-year-old Walker specifically, Southgate hinted his international career could be over with the emergence of Trent Alexander-Arnold and Aaron Wan-Bissaka.

He said: "Without getting Trent's [Alexander-Arnold] head too big, too quickly, he's got to be one of those we look to integrate and give more opportunity to. So, it's a bit like at a club, if we don't make a pathway, then when are you ever going to put them in?

"With Aaron [Wan-Bissaka], [we've got] a completely different kind of player so we've got Trips [Kieran Trippier] as a bit of cover around that and there's no point bringing Kyle in if the intention is not to start him in the games.

"He's a senior player and he'll value the rest and recovery as much as anything else. But, we could be in a different space in four weeks' time because, as I said, he's started the season very well, he's obviously got competition for his place at his club, and we've got that here."