The departure of two key Liberal cabinet ministers won't impact the party's chances in the 2018 election, Ontario's premier said Tuesday, downplaying the exit of two of her closest personal advisers in politics.

Kathleen Wynne was reacting to recent announcements that deputy premier Deb Matthews and Treasury Board President Liz Sandals will not seek re-election. Wynne thanked both women for their commitment to public service, adding that people sacrifice a lot to enter politics.

The premier said she hasn't given her cabinet a deadline to decide whether to stay or go in advance of the spring vote, and noted that the Liberals will have a number of strong candidates running next year.

"I have a strong team," she said. "We have wonderful candidates around the province who are signing on, who are going to put their names on signs and we're very, very grateful for that."

Sandals' and Matthews' decisions were the latest in a series of prominent Liberals opting not to run next year.

Last month, Economic Development Minister Brad Duguid announced he won't be seeking re-election. Former environment minister Glen Murray recently left government for the private sector, and Speaker Dave Levac, the Liberal representative for Brant, and Monte Kwinter, Ontario's oldest MPP, have also announced they won't seek re-election.

Meanwhile, various polls have put the Liberals behind the Progressive Conservatives and one survey even placed them third behind the NDP. Wynne, however, dismissed the party's standing in the polls, saying it's her job to focus on improving life in the province.

"The pollsters and the pundits will do their job and come the election next year the people of Ontario will make a choice based on the work that we've done," she said. "My job is not to analyze the polls. My job is to make sure that we work to provide opportunities and fairness to everyone across the province."

Wynne described both Matthews and Sandals as "friends, colleagues and advisers," but said both are women are also grandmothers and are eager to spend more time with their families.

"I completely, completely understand why Liz and Deb, who have been such, such solid giving people in their communities and in Ontario, that they would need to make a different decision at this point."

Matthews, who was elected in 2003, will stay as the representative for London North Centre and as advanced education minister until the election. She will also remain the Liberas' campaign co-chair through the election. But her announcement serves as an undeniable blow to Wynne, for whom Matthews has been a fiercely loyal deputy premier.

Sandals, 70, has stressed that her 30 years of service and her age were behind her decision to retire.

Wynne said Ontarians owe all who serve, regardless of party stripe, the chance to make such decisions with their families in mind.

"People give their time, they do an enormous amount, and then we need to, without rancour or criticism, let them make a decision that's good for their families and good for themselves," Wynne said. "I think that we owe that to public servants like Deb and Liz who have made a contribution."