Health concerns led five Tamil protesters to reluctantly end a 10-day hunger strike near Parliament Hill Sunday, as protest leaders promised larger crowds over the coming week.

Tamil-Canadians have lined the streets of downtown Ottawa in front of Parliament for nearly two weeks, demanding the federal government help broker a ceasefire in Sri Lanka's civil war and place sanctions on that country's government, which has battled Tamil militants for decades.

Organizers are predicting as many as 25,000 people in their ranks on Tuesday to coincide with Prime Minister Stephen Harper's return from the Summit of the Americas in Trinidad and Tobago.

Protesters are also optimistic they will have a meeting with MPs when Parliament resumes Monday.

The Tamil Tiger rebels are fighting to create an independent homeland for ethnic minority Tamils, who have faced decades of marginalization by successive governments controlled by ethnic Sinhalese. More than 70,000 people have been killed in the violence.