MP Aaron Gilmore appears to have threatened ''revenge'' on those who effected his downfall ahead of his valedictory speech in Parliament tomorrow.

After he resigned from Parliament last night, at least four people are understood to have received a text message from Gilmore this morning, including National Party members, advising them to learn the meaning of ''utu'' - the Maori word for revenge.

Those who have received messages include Whale Oil blogger Cameron Slater and Christchurch lawyer Andrew Riches.

Slater said he had received a message from Gilmore reading: ''Utu - You should look up the definition of that.''

Other variations included: ''Utu - You should learn what it means.''

Slater placed a screen shot of his text message on his Whale Oil Beef Hooked blog along with a post about Gilmore early this afternoon.

Riches confirmed he had received a similar text message from Gilmore but declined to comment further.

Gilmore, the National party's lowest-ranked list MP, was privately said to be seething last night and party members are anxious about what he might say in a valedictory speech planned for tomorrow.

Gilmore's father Garry Gilmore said last night that his son did not want to comment before addressing Parliament tomorrow, but when he did, it was going to be ''a big story''.

Gilmore issued a statement yesterday evening saying he was quitting with "a heavy heart".

National wanted him to go after his boozy antics in Hanmer Springs last month and allegations that he misled Prime Minister John Key's office.

An aggressive trail of emails also emerged last week, which had led to his departure from the Ministry of Business, Innovation and Employment (MBie) last year.

Gilmore was due to talk to party president Peter Goodfellow by phone yesterday afternoon, and Goodfellow wanted a meeting in Wellington today.

However, it is understood the party drafted in fixer and political consultant Simon Lusk to persuade Gilmore to go.

Gilmore has not picked up his cellphone since news of the Hanmer outburst broke and did not return a call this morning regarding the threatening text messages.

In his statement last night, Gilmore blamed the "intense pressure" media scrutiny had put him under.

"After taking counsel from colleagues and family in recent days, I have decided that to stay on in Parliament would only serve to cause my loved ones more upset, and cause me undeserved further stress, " he said.

He accused the media of attempting to discredit him.

"The attacks on my integrity have started taking a toll on those around me and this is unfair on them."

He said he had made mistakes. "I am human . . . I'm determined to learn from those lessons as I continue my life with more grace and humility."

Earlier, Goodfellow told a regional party conference in Whanganui that Gilmore had caused members and MPs "significant damage" and "overshadowed" the "excellent progress" made by the Government.

Gilmore was due to attend the conference but was persuaded not to. Instead, he flew to Christchurch, where he was spotted shopping with his children on Saturday.

He attracted no support from delegates at the conference, with one going as far as to call him "Silly Gilly". Goodfellow said last night that Gilmore had made a difficult decision. "Today he has put his loyalty to the party first."

He also acknowledged "Aaron's hard work and dedication".

"He has diligently carried out his duties at Parliament and in his home electorate. I wish him all the best for his future."

A spokeswoman for Key said: "Given the challenges Mr Gilmore has faced over the past 10 days or so, this is the right decision for himself, his family and the National Party."

Gilmore was accused of being rude to a waiter, asking, "do you know who I am?" and threatening to have Key intervene to get the waiter sacked.

Text messages contradicted Gilmore's version of events, causing Key and the party to withdraw their support.

On Friday, he was further discredited when the Ministry of Building, Innovation and Employment released emails detailing his bullying behaviour towards a Treasury official. His contract was not renewed as a result of the "inappropriate" messages.

Next on the National Party list is TV producer Claudette Hauiti, who stood as National's candidate in Mangere in 2011. Goodfellow said she was interested in coming to Parliament.