Mr Haniya led the radical movement to a landslide victory in January’s general election.
He is the clear favourite to be installed to head the government when parliament holds its inaugural session on Saturday.
Mr Haniya is thought to be more open to dialogue with Israel than many other Hamas leaders.
Israel has refused to deal with a government led by Hamas unless the group renounces violence and recognises Israel.
In an interview with AFP, Mr Haniya said Hamas would not renounce violence once it comes to power.
But he said it would work with the moderate Palestinian Authority President Mahmoud Abbas.
Mr Abbas is expected to use his speech to parliament on Saturday to remind MP’s and the new administration that everyone should respect “one weapon”, only the “lawful weapon” of the security services.
If he becomes premier he will also ask the incoming government to respect agreements signed with Israel.
A formal announcement has been delayed until the inauguration of the Palestinian Legislative Council at the weekend.
Travel ban
Israel has made clear it is unlikely that Mr Haniya will be able to visit the Palestinian Authority’s seat of government in Ramallah.
It said it would prevent any Hamas premier from travelling from the Gaza strip to the West Bank, by refusing to issue travel permits.
Teh premier will instead have to observe proceedings in the parliament via videolink from the Gaza Strip.
Israel also plans to impose economic sanctions against the Palestinians once Hamas forms government.
“The idea is to put the Palestinians on a diet but not make them die of hunger,” said prime ministerial adviser Dov Weisglass.