Protesters seeking redress for Mica-affected homes gathered outside a venue in Derry where the Taoiseach was giving a speech.
Up to 100 people gathered at the city's Playhouse theatre, with many carrying placards calling for 100% redress for families.
They are mostly holiday home owners from Northern Ireland who are not covered by the redress scheme.
Micheál Martin spoke to several protesters before going in to deliver his speech at an event organised by the John and Pat Hume Foundation.
The Mica Action Group says Northern Ireland homeowners must be included in the redress scheme.
It also said there are issues to be resolved about the scheme to ensure people are not left out of pocket due to damage from defective bricks.
Thousands of homes have crumbled because of mica, a mineral which absorbs water, causing walls to crack.
Earlier, the Taoiseach said he was disappointed that a meeting tomorrow with Letterkenny Chamber of Commerce had to be called off when the hotel said it could no longer accommodate it.
Mica families had planned a protest outside the Radisson Hotel in Letterkenny.
Mr Martin said the enhanced redress scheme had resulted from meetings he and others had held to discuss people's concerns with the scheme.
He said he hoped the legislation required to underpin the €2bn redress scheme would be published this month and he hoped to have it passed by the summer recess.
The Taoiseach said he had no difficulties meeting Mica-affected families and would do so again in the future.
People whose homes are affected by Mica protest as Taoiseach arrives to give a speech in Derry @rtenews pic.twitter.com/k208efLRi9
— conor macauley (@TVconormac) April 1, 2022
The Donegal Mica Action Group claimed it was excluded from the Taoiseach's original itinerary.
The group said it had asked to meet the Taoiseach on his visit to Donegal and when it appeared it was not included it decided to hold a "dignified protest" outside the hotel to get its message to Mr Martin.
The group said that given the scale of the mica crisis, the thousands of families affected and the serious issues it has with the revised redress scheme, it should have automatically been included in the Taoiseach's itinerary.
Following the publication of the revised redress scheme, the group submitted dozens of questions on it and expressed frustration that these questions have not yet been answered.
Spokesman for Mica Action Michael Doherty said it was then offered a meeting with the Taoiseach, but at a time that had already been allocated to another organisation, so it was being "shoe-horned" in and another group, which had put a lot of preparatory work into its meeting, was being displaced.
It is understood that yesterday when the hotel said it could not facilitate the lunch, thought was given to finding another venue, but the Taoiseach's department said it was not going to happen and the meeting was cancelled.
Kristine Reynolds, President of Letterkenny Chamber of Commerce, issued a statement saying the event would not go ahead "following consultation with the department".
The meeting with the Taoiseach had been planned for some time and the chamber said it was extremely disappointed that it would not happen.
It said it wanted to use the meeting to "emphasise the economic needs of the county and region including Mica redress".
Additional reporting Eileen Magnier, PA
