The throne speech opening the new legislative session will focus on retirement security and the quality of life the government wants people to have, he said.
They want to team up with other provinces on such issues as creating a provincial pension plan to supplement the Canada Pension Plan, which the federal Conservatives have refused to enhance, he said.
"Those kinds of initiatives show nation-building, it's also about leadership, but it's also recognizing that Ontario's place in the federation is critical," Sousa said.
"And we want the federal government to respect that too in terms of investing in those strategic programs and opportunities that exist in the province for everyone's benefit."
The speech, entitled "Building Ontario Up," will outline the Liberals' plan to grow the economy, including job training programs and continuing a 30 per cent discount on tuition for some post-secondary students.
To promote Ontario overseas, Premier Kathleen Wynne is planning to make a week-long trade trip to China this fall, the Liberals said.
The speech, to be read by departing by Lt.-Gov. David Onley, will be the first glimpse at the Liberals' agenda after winning a majority of seats in the legislature. But it will sound very familiar.
Most of their priorities were laid out in the budget that triggered the June 12 election, which the Liberals plan to introduce again.
It includes doling out $29 billion over 10 years to build public transit and other transportation infrastructure and another $2.5 billion in corporate grants to bring and keep businesses in Ontario.
Government house leader Yasir Naqvi said the Liberals will work with the opposition parties, even though they no longer need their help to pass legislation.
"They were a very important part of the entire process, but of course we also have a mandate from Ontarians," he said.
"That centres on going out and creating good paying jobs, investing in transit and transit infrastructure and making sure that there is a secure retirement for Ontarians."
The Liberals have also promised to eliminate Ontario's $12.5-billion deficit in three years, which will require them to put the brakes on government spending.
The speech will reiterate their commitment to being "fiscally responsible" and their "unwavering commitment" to balance the books in 2017-18, they said.
It will also lay out the role of newly minted Treasury Board president Deb Matthews, who will have to find the savings to meet that deadline.
The Progressive Conservatives are facing leaner times too. Their crushing election defeat saw them lose nine seats — a failure they've blamed on an ill-fated promise to cut 100,000 public sector jobs to help slay the deficit in two years.
Tory Lisa MacLeod said she's not expecting any surprises in the throne speech.
"The election results are still very fresh in everyone's minds and I think people are still digesting on our side what those results mean, and I think that has given Ms. Wynne a mandate," she said.
"That's not to say that there won't be opportunities for us to critique her policies, but I think we know very much the position she's in and where she wants to take the province."
Tim Hudak, who stepped down Wednesday as PC leader, was nowhere to be seen during the swearing-in ceremony for new and re-elected members of the provincial parliament.
He's promised to stay on as an MPP representing his riding of Niagara West-Glanbrook.
Jim Wilson, a health minister under former premier Mike Harris, was chosen serve as interim leader until a new one is elected by party members.
Liberal Dave Levac was re-elected as Speaker, the often thankless job of playing impartial referee to unruly MPPs in the legislature.
He beat his colleague Shafiq Qaadri, Tory Rick Nicholls and New Democrats Paul Miller and Cheri DiNovo for the job.
An emotional Levac said he was extremely humbled by the vote of confidence from all three parties.
"There's something going on right now called the beautiful game," he said, referring to the FIFA World Cup soccer championship.
"This is the beautiful place. It represents who we are as a province and I'm humbled by having this opportunity to serve you."
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