THESSALONIKI, Greece (AP) — Greece’s prime minister promised Friday to extend an existing wall across all of the country’s land border with Turkey as he campaigned for the country’s general election.

Prime Minister Kyriakos Mitsotakis, who called the May 21 election earlier this week, presided over a ceremony to sign his center-right government’s decision to nearly double the length of the existing steel border wall over the next year.

The wall currently spans 37.5 kilometers (25 miles), and the government plans to extend it by 35 kilometers over the next 12 months. More than 100 kilometers of wall will be added to that by 2026, government officials said.

Border security remains a high-profile issue in Greece due to long-standing disputes with Turkey and a mass migration of refugees and migrants into the European Union during 2015-16 that largely was triggered by war in Syria and Iraq.

The control room of the new camera systems in Nea Vyssa. Greece strengthens its surveillance capabilities to fight the increased refugee and migrants flows from Turkey. (Nicolas Economou/NurPhoto via Getty Images)

Mitsotakis and other officials accused their political opponents from the left-wing Syriza party of trying to undermine the project and to block the government’s attempt to obtain European Union funding for it.

“I would like to express my regret that there are political forces in Greece today that are fighting this project,” Mitsotakis told supporters during his campaign stop in Orestiada, a town near the Greece-Turkey border.

“Let them state their position clearly: Will they tear down the wall that we have already built and return to a policy of open borders? Or will they preserve it and help secure Greece’s borders?” Mitsotakis asked.

Syriza officials accused the government of misrepresenting the opposition’s position, adding that the EU’s executive commission already ruled out providing direct funding for border walls.

“We are not going to tear down anything,” European Parliament Vice President Dimitris Papadimoulis, who heads the Syriza delegation in the EU legislature, told Greek radio station Real FM. “And of course, we support EU funding for border security needs, like funds for night vision cameras and coast guard vessels.”

Papadimoulis accused the government of pandering to far-right voters and trying to distract attention from a deadly rail disaster last month that has triggered public anger and cut into Mitsotakis’ lead in opinion polls.

The government argues the wall has functioned as an effective deterrent against illegal migration, helping prevent more that 250,000 crossings at the land border last year.