The Rev Ian Paisley "wants to do a deal by March 26th", according to anti-St Andrews Agreement unionist Bob McCartney.
The United Kingdom Unionist Party leader was speaking at the launch of his party's manifesto. His party will field 13 candidates, with Mr McCartney standing in six constituencies himself.
He said he believed "family and other factors" would mean Dr Paisley would form an executive with Sinn Féin.
"For a long time now he [Paisley] has been knocking at the door of the establishment and now I believe he wants to be let in."
Mr McCartney attempted to clear up confusion about what would happen should he be elected in more than one constituency, saying he would give the additional salaries he would get to charity.
He also said if he were elected to several seats and Northern Secretary Peter Hain tried to stop him casting more than one vote, he would take Mr Hain to court.
The DUP has accused Mr McCartney of being a "vote-splitter" by taking its votes away and helping Sinn Féin in the process. He rejects this claim.
"How can a party that is totally dedicated to preventing Martin McGuinness, Gerry Adams and company ever being in government be helping them, when a party such as the DUP, which has reversed the policies of a lifetime to welcome them, is not helping them?"
The Workers' Party called for the restoration of Stormont during its manifesto launch, while also calling for non-payment of water charges.
It said it would also end the practice of designation in the Assembly, which, it said, was the cause of "political paralysis".
Meanwhile, DUP deputy leader Peter Robinson has welcomed the Conservative Party's pledge to remove the designation system in the Assembly.
"We hope that the sentiments expressed in this area in the Conservative Party manifesto are not mere rhetoric and will be implemented if the party wins the next election."
Dawn Purvis, PUP leader and candidate for East Belfast, said she was "delighted" to attend Tuesday's question-and-answer session with first-time voters at Lagan College.
"Politics in Northern Ireland often lacks new ideas, so who better to provide those ideas than our young people?
"We should listen and better value our young people and first-time voters. This event provided just that opportunity, and it should not be squandered."
Marion Smith, UUP candidate for North Down, has made a plea for a good turnout on polling day. "People who want to see progress must get out and vote on the day."
Meanwhile, North Down Alliance candidate Stephen Farry has criticised the SDLP over its proposals for a referendum regarding the Border.
"The last thing that Northern Ireland needs is a Border poll."