Brisbane Lord Mayor Campbell Newman, who was left the largest Liberal standing after Labor's federal election victory in November, has urged party delegates to say yes ahead of this weekend's merger vote.

Cr Newman joined four other Liberal politicians who signed their name to a letter composed by federal shadow minister for trade, Ian MacFarlane, that will be sent to delegates today.

"We are resolute in our commitment to have the new party form the next government in Queensland," the letter states.

"This merger and this outward focused constitution will give us the best opportunity to be a credible and competitive non Labor alternative.

"The people of Queensland deserve to be given a real choice at the next election."

State leader Mark McArdle and his deputy, Tim Nicholls, as well as deputy mayor Graham Quirk, also signed the letter.

Cr Newman has so far been reluctant to comment publicly on his party's electoral woes or the proposed merger, which could take place next week if Saturday's vote falls in favour of creating a new Liberal National Party (LNP).

Mr MacFarlane said a failed merger would give Labor its best chance of winning the next state election.

"A Yes vote provides a future and a plan for us to win government by securing the support and trust of Queensland voters," he wrote.

"Let's always remember we exist as a political party to serve the people of Queensland and Australia and to deliver good government."

Both parties will spend the week ironing out final details.

Queensland Nationals state director Michael O'Dwyer said he was confident his party's members would back the merger.

"Our members will decide and I'd hate to put words in their mouths but all communications we've had is that our members are overhwhelmingly positive that this just has to happen," Mr O'Dwyer said. 

Weekend reports that federal Liberal president and former Northern Territory chief minister Shane Stone was set to take on the LNP's presidency could not be confirmed.