The finance minister of Scotland’s devolved government resigned on Thursday after admitting he “foolishly” sent hundreds of sometimes flirtatious social media messages to a 16-year-old boy.

Derek Mackay, 42, resigned on the day he had been scheduled to deliver a budget statement for the Scottish National Party government.

“I take full responsibility for my actions. I have behaved foolishly and I am truly sorry,” Mackay said in a statement after the Scottish Sun published details of the 270 messages.

“I apologise unreservedly to the individual involved and his family,” he said.

SNP leader and Scottish First Minister Nicola Sturgeon said she accepted Mackay’s resignation.

“Derek has made a significant contribution to government, however, he recognises that his behaviour has failed to meet the standards required,” Sturgeon said.

In the messages, Mackay called the boy, who plays rugby, “cute” and offered to take him to a rugby match.

Mackay, who is openly gay, had never met the boy, the messages suggested.

Murdo Fraser, a member of the Scottish parliament for British Prime Minister Boris Johnson’s Conservatives, tweeted that it was “a huge blow for @NicolaSturgeon to lose such a key member of her government at such a crucial time – and one tipped as her successor.”