But when Qalqiliya's water supply is interrupted, its electricity falters or its sewage system backs up, al Masri plans to put his political beliefs aside, reach for the telephone and call his enemies - the Israelis - for help.
"We do not have any objection to sit down and talk with them," said al Masri. So long, he added, as their discussion is limited to municipal chores controlled by Israeli occupying forces. "There will not be any political relationship between us," he insisted.
Even so, a conversation between Israel and Hamas about garbage pickups would have been nearly unimaginable a few months ago, but in the changing political landscape of the Middle East it is about to become a necessity.
In the weeks before Palestinian municipal elections early last month, Hamas - known locally as the Islamic Bloc for Change and Reform - campaigned on a platform of honesty, accountability and transparency. It won a third of the seats contested in 84 villages and cities in the West Bank and Gaza. Voters fed up with corruption in the Palestinian Authority turned to Hamas, which has earned admiration for its efforts organizing schools, clinics and other community services.
In Qalqiliya, Hamas candidates swept all 15 council seats once held by the Palestinian faction Fatah, whose head is Palestinian leader Mahmoud Abbas.
If the Hamas-controlled local councils want to keep their promises to improve public services, however, the councils will need to work with the Israeli military, creating an awkward situation for both Hamas and the Israelis.
Hamas doesn't recognize Israel's right to resist. Likewise, Israel, along with the United States, considers Hamas a terrorist organization and holds it responsible for killing hundreds of Israelis in suicide bombings, rocket attacks and other violence.
Officially, Israel forbids any contact with Hamas.
"It's really complicated," Adam Avidan, spokesman for Israel's military government in the West Bank, said of the prospect of meetings with elected Hamas officials. "We never had this problem before."
But Avidan expects there will be regular contact between the Hamas-run municipalities and Israeli authorities. "We are not going to meet on political issues," he cautioned. "What we are going to do is to work on civilian matters."
Avidan noted two cases of contact so far.
In Jayus, near Qalqiliya, a Hamas councilor negotiated with Israeli authorities to open a gate across a barrier that was closed by Israel for security reasons but that Jayus farmers needed opened to reach their fields.
In Silat ad-Dhaher, a village near Jenin, a newly elected councilor struck a deal with Israeli authorities to stop village children from throwing rocks at Israeli soldiers in exchange for lifting curfews on the village.
Where these contacts will lead is anybody's guess. Although both sides insist that their meetings will be strictly business, Avidan expects their relationship will deepen.
"Personally, I think it will lead to other contacts. It's natural that it will happen. You start out with small things, and we will talk more and more," he said.
Hamas, too, acknowledges uncertainties about the future. "There are a lot of question marks in front of Hamas right now," said Ghazi Hamad, a spokesman for Hamas in Gaza.
Israeli authorities have not agreed to work with all Hamas members, making a sharp distinction between Hamas party members and armed militants.
"We do have red lines. People we know who are dealing with terror, we are not going to work with," Avidan said.
In Qalqiliya, there has not been an occasion to speak with the Israeli authorities, said al Masri.
If the meetings take place, al Masri doesn't expect Israelis to be too pleased with the people the residents of Qalqiliya elected to office. Of the municipal council's 15 members, 13 have spent time in Israeli prisons in the past two decades. Qalqiliya's new mayor, Wajih Qawwas, is in jail on administrative detention, as he has been for the past 30 months. He is expected to be released next month.
Until then, al Masri is in charge. A 44-year-old pharmacist with tired eyes and a neatly trimmed beard, he sat in the mayor's office on a recent morning plowing through a day of meetings with a tiny cup of sweet coffee by his side. His council has an ambitious agenda, including an overhaul of the city administration, which had been unresponsive to residents' needs.
"Fatah was unable to provide the community with a plan for development," al Masri said. "There were problems with corruption, bad management, nepotism and greed."
The council also plans to open a city park, improve the water supply to one of the city's neighborhoods, and build a hospital and a school.
Whatever Hamas' good intentions on the municipal level, its political ambitions are deeply troubling to Israel, which fears that the Islamic organization's leadership will spoil any chances for peace.
Speaking at a recent forum in Jerusalem, Giora Eiland, national security adviser to Israeli Prime Minister Ariel Sharon, said that regardless of efforts by the secular, Fatah-led Palestinian Authority to quell violence, those efforts could be undermined by Hamas, making it difficult for Israel to enter negotiations with the Palestinians.
Hamas, Eiland said, remains committed to the destruction of Israel and will likely initiate a new cycle of violence after the Palestinian parliamentary elections and Israel's evacuation of all settlements in the Gaza Strip and four others in the West Bank. "Hamas is a terrorist organization by its very nature," he said.
Israel remains critical of Abbas, the president of the Palestinian Authority, for failing to confront Hamas and disarm it. Abbas, however, is betting that by inviting the militants to become part of the political process he can persuade them to achieve their goals through peaceful negotiations rather than violence.
Some Hamas leaders have said they would be willing to accept a Palestinian state in the West Bank and Gaza Strip. But just how flexible Hamas would be on the location of borders, the right of return for refugees and other issues is not clear.