Jerusalem Mayor Uri Lupolianski voiced support on Sunday for a plan to construct high-rises in the center of the city and to develop the remaining open spaces on the periphery of the capital instead of expanding the city westward. "There are many plans for building within Jerusalem, including high-rise construction, which is an option, and now is the time to put these plans into action," Lupolianski told the press after a lunchtime meeting with the heads of environmental groups in which they discussed alternate building plans. The meeting came 48 hours after Lupolianski, in a stunning about-face, announced that he had decided to freeze the Safdie Plan to build 20,000 housing units on more than 26 square km. of woodlands west of Jerusalem. Asked to explain the decision, Lupolianski said the Safdie Plan would take too long to ameliorate the city's housing shortage, stressing that even if it went forward no new homes would be built until 2020. "We cannot mortgage the present for the future," he said. The heads of the environmental groups, who led a two-year campaign against the Safdie Plan were hard pressed Sunday to explain the mayor's change of heart, but welcomed the move nonetheless. "We were completely taken by surprise," said Naomi Tsur, the head of the Society for the Protection of Nature in Israel. "It seems there is such a thing as a good surprise." Tsur said the fact that a majority of Jerusalem city council members opposed the proposal might have contributed to the mayor's decision to freeze the plan. The Green groups must now come to agreement with the mayor over the plans to build additional high-rises in central Jerusalem, something that they have opposed in the past but are now likely to stomach as the lesser of two evils. The environmental groups had released a study indicating that up to 60,000 apartments could be built in the city. Advocates of the Safdie Plan had said there was almost no room left to build in Jerusalem. "The mayor saw that there was indeed potential and a plan to build in the city, and not just empty talk about it," said Uri Bar-Shishat, the author of the study. "These groups did not just come and say no," they provided an alternative, Lupolianski said. A earlier plan to build eastward toward the West Bank settlement of Ma'aleh Adumim was frozen due to US opposition. Tens of thousands of young people have left Jerusalem since the 1980s. The primary reasons cited by people who left were a lack of job opportunities and affordable housing.