TORONTO -- Ontario Premier Doug Ford has slammed the province’s teachers' unions again, saying they are constantly attacking the government and are part of the problem in agreeing on a back-to-school plan.

Ford made the comments on Monday at Queen’s Park after being asked about the plan to reopen schools in September. The news conference also came after the government rejected Toronto District School Board (TDSB) proposals for reopening both elementary and secondary schools, claiming plans for both don't give students enough time in class.

"They constantly want to attack," Ford said. "I'm begging the unions, just work with us, like, man, come on, we work with everyone, absolutely everyone and just them, why? It's not a coincidence."

"Why don't you be part of the solution, instead of a part of the problem. Everything you've asked, we've changed it."

Ford said his government has accepted multiple requests from the unions, including providing funds for better ventilation in classrooms, more sanitation and access to reserve funds. He claims it's time for the unions to be flexible. 

"Work with us. Anything they ask, we do. We want just a little bit more and you shoot it down. It’s just not fair."

Since the government's back-to-school plan was released, parents and school boards have criticized the lack of physical distancing standards in the elementary grades, something called for in multiple reports published by the province's leading epidemiologists and pediatricians.

In response, Education Minister Stephen Lecce authorized boards to dip into their reserve funds to hire more teachers to increase physical distancing, and granted $50 million to upgrade ventilation systems in schools but stopped short of mandating smaller class sizes. 

Lecce said allowing boards to dip into reserve funds "unlocks' $500 million in funding for select boards across the province. Boards that do not have access to these reserve funds will be awarded a "top up" of $11 million.

But TDSB spokesperson Ryan Bird said the Ontario government blocked their board’s plan to reduce the average size of classrooms to 15 students for kindergarten to Grade 3, and 20 students for Grades 4 to 8, which would have seen the board hire 200 additional teachers at a cost of $20 million.

The rejection means parents still do not know the exact size of their children's classes or how or when the school day will start or end – with three weeks left before the scheduled start of the school year.

Meanwhile, the teachers' unions said last week that they are considering legal action over the province’s back-to-school plans.

Speaking to CTV News Toronto, the Ontario Secondary School Teachers' Federation (OSSTF) said the union was "exploring with counsel what tools we have to keep members safe."

OSSTF President Harvey Bischof said there is no single “silver bullet” in the plan that the union takes issue with, but rather a "constellation" of issues.

"We're investigating how we can support our members legal right to a safe workplace," Bischof said.

Similarly, the Elementary Teachers' Federation of Ontario (ETFO) as well as the Ontario English Catholic Teachers' Association (OECTA) have both said they are exploring all their options.

With files from CP24's Chris Herhalt.