Tommy Wright has quit as St Johnstone manager after seven years in charge, saying he "needed a break".
The 56-year-old said the end of this season would have been a "perfect time" to leave, but now felt "appropriate".
The Scottish Premiership club say talks had been ongoing for some time about the "much valued" Wright's departure.
The Northern Irishman, who still had two years of his deal to run, has been linked with the vacant managerial post with his country.
Assistant Alec Cleland is in interim charge, with the club beginning their search for a permanent manager once it becomes clear when football will return.
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"It was something that was being considered for a while," said Wright, who explained that the idea of him leaving this summer was first mooted two seasons ago.
"We made the decision that we'd see if in the next couple of years we could bring the age of the squad down and then it might be time for me to move on. Fortunately we've done that.
"I felt that when you're at a club for such a length of time sometimes there just comes a point when I needed a break. It's a tough job. It is 365 days a year and it is 24 hours a day.
"I just felt, particularly this season, if we could have got to the end of it and done well then it would be the perfect time for me to leave the club in a really strong position."
Wright joined the club in November 2011 as assistant to Steve Lomas, and took charge in June 2013.
He led them to their first Scottish Cup win in 2014, as well as European campaigns and several top-six finishes an was the third longest-serving manager in the SPFL.
St Johnstone were seventh in the Scottish Premiership when the season was halted on 13 March.
"I'm extremely proud of the situation I leave the club in," Wright added.
"There are lots and lots of memories. Even things that people don't think about like the loads of young players I gave their debut to. Over the last couple of days I've had time to reflect and I've remembered people like Scott Brown, Zander [Clark], Jason [Kerr], Liam Gordon, Ali McCann.
"Even those things, when you sit back and take a look at the bigger picture, give me so much pride."
'Inevitable this day would come'
Off the Ball presenter & St Johnstone fan Stuart Cosgrove:
Tommy's been a legend for St Johnstone. No-one wanted to contemplate the day that he would go but it was inevitable that one day he would. Over the years, he been living in an apartment in Perth, at times on his own while his wife went back to their home in the suburbs of Belfast.
I suspect what has happened is that Tommy's been talking to the club about when would be the right time. I think he's gone back home, he's sat down with his wife, and he's thought, 'you know what, now is the time'.
Tommy has done a deal now. His contract with St Johnstone is going to be concluded. However, he might be somebody who they might keep on as an adviser. He's so well-loved.