Alliance leader Naomi Long has said the current general election campaign is “one of the worst” she has ever fought in terms of “smears and lies”.
She was speaking as she helped launch her party’s manifesto at a Belfast hotel.
In recent weeks, banners attacking a variety of politicians and parties have appeared in North and South Belfast and in North Down.
The party is standing candidates in all 18 seats in Northern Ireland.
It had no MPs in the last Parliament.
Mrs Long told BBC News NI: “I think it is one of the worst elections that I have ever fought in terms of the levels of smears, the levels of lies. The levels of discrimination.
“I think it is just a fact now of the kind of culture that we see in politics where we treat people with disrespect where people are not allowed to differ and have a disagreement.”
Mrs Long, who won East Belfast in 2010 but lost it in 2015, refused to be drawn on what her target was in terms of winning seats.
She said: “Of course I want to win seats and of course we are ambitious to be represented at Westminster.
“It is the only level of government where we don’t have an elected representative.”
The party remains confident that it can win parliamentary seats next month.
Earlier this year, Mrs Long became the party’s first MEP and Alliance secured gains in the local council elections.
The 40-page manifesto, entitled Demand Better, examines Brexit, Stormont, governance and transparency, work and welfare and climate action.
The party wants a fresh EU referendum with the option to remain in the EU.
It says there should be a special deal for Northern Ireland and that the whole of the UK should remain in the single market and the customs union.
“Brexit must not become an orange and green issue,” Mrs Long said.
The Alliance leader added that her party was pro-Remain.
“Our future lies at the heart of the EU,” she said.
In relation to restoring devolution in Northern Ireland, Alliance say any future inter-party talks should be “time-bound” and should be chaired by an “independent mediator”.
Mrs Long said that if there is no agreement by 13 January 2020, there should be “fresh elections”.
On the issue of securing local political agreement, the Alliance leader said “the DUP and Sinn Féin must compromise”.
Alliance would like to see a new civic forum made up of local politicians and citizens.
The party says there should be “full transparency of political donations” and it would like to see proportional representation for elections to the House of Commons and a directly elected House of Lords.
Alliance would also like to see 16-year-olds allowed to vote in elections.
On work and welfare issues, Alliance would like to see the repeal of the bedroom tax and an overhaul of bereavement benefits.