The intrigue around Senator Stephen Conroy’s exit from parliament has been heightened by Labor leader Bill Shorten’s revelation that Mr Conroy gave his resignation notice to him via text message.

Mr Shorten was attending a conference in Montreal when he received the message, but was unable to reply before Senator Conroy tabled his statement to the Senate on Thursday night.

“We can have a debate about who should have known what, when, but for me, and for the Labor party, we wish Stephen Conroy well,” the Opposition Leader told reporters in Washington.

Firebrand Conroy was as Machiavellian with his resignation as he has been with his factional enforcing throughout his 20-year parliamentary career.

When it became clear on Friday morning that he tabled – but not read out – his resignation speech in the Senate late the night before, speculation immediately flared over the real reason the high-profile senator had quit.

He had just been re-elected in July, showing no signs he intended to leave politics before completing his new six-year term.

This led some to speculate on Friday that he had quit after the election in order to circumvent a preselection process for his successor and handpick his own replacement to be endorsed by the Victorian State Parliament.

Others talked of a multi-national corporation offering him a huge salary for strategic trade advice.

And the ongoing saga involving Australian Federal Police raids on his office over leaks from the National Broadband Network was another reason proffered for his resignation.

The moment Stephen Conroy resigned. “I seek leave to table the rest of my contribution so we can move on.” #auspol pic.twitter.com/pqwIMvaH6T

— Political Alert (@political_alert) September 16, 2016

But sources close to the senator say “personal family matters” have caused the outspoken Labor stalwart to say goodbye to Canberra.

Family issues featured prominently in Senator Conroy’s speech, with him acknowledging the toll political life takes on spouses and children.

He said that in addition to his absence for almost half of each year, one of the things his wife Paula Benson and their nine-year-old daughter Isabella had to deal with was being ridiculed by association.

“Noting the glances and scowls as you walk down the street together. Explaining to my young daughter why people have shouted abuse at her Daddy in the street,” he said.

Plibersek didn’t know Conroy had resigned. Photo: AAP

“Being immediately judged as you explain what your partner does or who he is based on the media image.

“I’m sure you would all agree that there should be a special place in hell for those who judge women based on their spouse’s work.”

Spending more time with his daughter, he insisted, was a motivating factor for leaving politics.

“When you resent being in Canberra because you are missing your daughter’s soccer training it is time to retire from the federal parliament,” he said.

Isabella was born in 2006 after Senator Conroy and Ms Benson used a surrogate mother and separate egg donor.

They did this because Ms Benson had suffered ovarian cancer and was unable to conceive or carry a baby. The birth was noted as an Australian first.

Conroy: ‘Shorten is a future PM’

The resignation takes effect at the end of this month, meaning Senator Conroy will be gone before parliament returns in October.

He praised many of his colleagues, but none of them knew of his intention to leave.

Acting Opposition Leader Tanya Plibersek was caught completely unawares when asked about it during a morning press conference.

Opposition Leader Bill Shorten, who is in Canada, subsequently issued a statement saying he had spoken with Senator Conroy.

Mr Shorten and Mr Conroy are close friends. Photo: AAP

Describing him as one of his oldest friends, Mr Shorten said the senator was a champion of the Labor Party who had always offered him fearless good advice.

“I have spoken to Stephen and he told me he has decided it is time to put his wife and daughter, who he loves so much, first. I admire and respect his decision,” the Opposition Leader said.

The retiring senator described Mr Shorten as the Prime Minister in waiting, who should not be underestimated.

Senator Conroy has been minister for broadband, communications and the digital economy and minister assisting the prime minister on digital productivity.

In Opposition he has also served in shadow ministries, including special minister of state, defence, sport, trade and finance.

He rates the NBN as his greatest achievement.

The AFP confirmed the NBN leaks investigation remained ongoing and would shortly be considered by the Parliamentary Privileges Committees.

Mr Conroy’s full resignation speech: