Scott Brown has expressed concern at the timing of Scotland's summer friendlies and said they may not be ideal for the national team's Celtic contingent.

The Scottish FA, who learned on Monday that Michael O'Neill had rejected the opportunity to become the new national team boss, has announced that the squad will travel to play Peru on May 29 and Mexico three days later.

Should Celtic go on to retain the Premiership title, their players would be in Champions League qualifying action from July 10/11.

Recent Scotland squads have included a sizeable number of Celtic players, with Brown, Craig Gordon, Kieran Tierney, Stuart Armstrong, Callum McGregor, James Forrest and Leigh Griffiths all involved.

Brown pointed out that getting a good rest at the end of the season was essential for players' wellbeing.

"The holiday time is huge," Brown said. "Last year we got six days and came back in and went straight into the Champions League qualifiers.

"We will probably get a week and a half this year.

"It is getting not so good in the holiday but you get the opportunity to play for Scotland.

"There will be a new manager in and he will obviously want to see everybody.

"So there is a couple of friendlies coming in March and June as well, it will be good for him but maybe not so good for all the Celtic lads.

"We will see what happens when it comes. There are a lot of games from now until then, you never know what can happen."

Brown's concerns were echoed by Celtic assistant manager Chris Davies.

"The manager (Brendan Rodgers) will look at that but I don't know what we will do," he said. "But it is the national team so we will see what happens.

"You do need a break, the players need a break.

"You cannot play 12 months non-stop and expect at a big club, the level of intensity, you want to be in the Champions League, it is impossible for players to play for 12 months."