MPP Glen Murray has resigned as minister of training, colleges and universities, signalling a possible run for the leadership of the Ontario Liberal Party.

Murray told his Twitter followers on Saturday he had submitted his resignation to Premier Dalton McGuinty.

The former Winnipeg mayor said he will reveal more details at a news conference on Sunday morning.

He has served the Toronto-Centre riding since he won a byelection in 2010 to replace George Smitherman.

Community and Social Services minister John Milloy will add Murray’s portfolio to his own and will be sworn in early next week.

Murray joins longtime cabinet minister Kathleen Wynne, who resigned her posts as minister of municipal affairs and housing and minister of aboriginal affairs on Friday and told McGuinty she would enter the leadership race. She will speak to the media on Monday evening.

Health Minister Deb Matthews, former cabinet minister Sandra Pupatello and ex-MP Gerard Kennedy are also reportedly considering a run and have until Nov. 23 to decide.

Finance Minister Dwight Duncan, Education Minister Laurel Broten and Economic Development Minister Brad Duguid have said they won’t enter the race.

The party will choose its new leader at a convention on Jan. 25, 2013.

On Oct. 15, McGuinty announced he would step down as Liberal leader and suspended the legislature.