Guelph MPP and Treasury Board President Liz Sandals has announced she will not run in the 2018 provincial election.

Sandals made the announcement Friday in a statement sent to the media. She said she has served in elected office for 30 years and is now 70 years old and it's time to retire. 

"After a summer of discussion with my husband and children, I have made the difficult decision to retire – and so I will not be running in the next provincial election," Sandals wrote. 

"I will continue to serve as the MPP for the riding of Guelph until the end of the term, and at the premier's pleasure, I would be honoured to continue to serve in her cabinet."

Premier Kathleen Wynne issued a statement Friday calling Sandals "one of the most competent, caring people I've ever worked with."

"I will miss Liz's steady hand, wise counsel and friendship. Her years of experience and strong set of values have always been a guiding light for me and our whole team," Wynne wrote, adding the government will rely on Sandals's wisdom and leadership over the coming months.

"Concluding a career of public service is never an easy decision, but after 30 years in elected office, Liz Sandals can retire next year knowing that she has made a positive difference in her community and in people's lives all across our province."

Liberals losing incumbents

The announcement comes the day before a long weekend and the same day deputy premier Deb Matthews, the Liberal MPP for London North Centre, said she is also leaving politics.

"The time has come for me to step aside," Matthews wrote in a statement to the media. "Ontario is a better place today than it was in 2003. I am proud to have been part of that change." 

A number of high-ranking Liberals have chosen not to run again in 2018. In September, Economic Development Minister Brad Duguid said he would not seek re-electionn while Speaker Dave Levac, who is the Liberal representative for Brant, and Monte Kwinter, Ontario's oldest MPP, have also announced they will not run.

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Guelph MPP Liz Sandals, left, with Ontario Premier Kathleen Wynne in 2014 when Sandals served as education minister. (The Canadian Press/Chris Young)

Faith in Wynne

Sandals was first elected MPP of Guelph in October 2003. She served in cabinet as the minister of education in 2013 and 2014 and most recently as President of the Treasury Board. She has also served as a parliamentary assistant on a number of ministerial portfolios.

In her statement, she thanked both Premier Kathleen Wynne and former premier Dalton McGuinty, her caucus colleagues, her family and her constituents and volunteers in Guelph.

"It has been an absolute privilege to represent you for the last 14 years, and I'm so proud to have fought for our community for so many years," she wrote.

Sandals called the decision to not run "challenging."

"While I'm ready to be a full-time grandmother, I've never had more faith in Premier Kathleen Wynne and the Ontario Liberal Party," she wrote. "I believe that the Ontario Liberals will win the next election because Premier Wynne offers bold, progressive leadership."

Wynne was in Kitchener on Friday to tap the keg for the start of Oktoberfest.