The SDLP launched its election manifesto in Belfast today.
The Irish nationalist party's leader Margaret Rictchie said Westminster is vital to creating both a strong economy and society.
The party held three seats in the last parliament and faces a strong challenge from Sinn Fein across the province.
"This election is about grown-up, bread and butter politics and coming forward with the ideas that will improve people's lives in very difficult times," Ritchie said.
"We will not enter a tribal contest with unionists or a slanging match with other nationalists."
Earlier this week the SDLP rejected an electoral pact with Sinn Fein in the Fermanagh and South Tyrone constituency, where the two main unionist parties have decided to field a joint candidate.
Ritchie said her party will campaign for a "prosperous, increasingly independent economy that lifts the lives and wellbeing of all, a genuinely shared society and in time, a united Ireland".
"A shared future is a cornerstone of my agenda as Minister for Social Development and a foundation stone for my leadership of the SDLP," she said.
Ritchie was elected leader in February.
"The mutual tolerance and co-existence we currently have are just not enough. We will aim higher.
"Not just by aspiring to genuine sharing and mutual respect, but by applying radical new ideas things happen in housing, education, regeneration, community funding and cultural expression."
Ritchie said the SDLP "could not be more different from our political opponents" on jobs and the economy, a new reconciled society and a "credible approach" to the future politics of Ireland.
"We alone can deliver this vision. And Westminster has a key role to play.
"We have the people who can turn these ideas into realities. And to do so they will have to be there."
She also attacked Sinn Fein's abstentionist policy at Westminster.
"Those who claim that Westminster doesn't matter or that there is no need to actually be there are simply wrong.
"It sets the total Northern Ireland budget and decides on many other crucial social and economic issues which are not devolved. And it negotiates for us in Europe."
The SDLP is fielding candidates in all 18 Northern Ireland constituencies.
