The closure of the only commercial crossing point in the Gaza Strip may cause severe losses to Gaza farmers, a farming society warned Tuesday.

The Society of Palestinian Flower and Strawberry Farmers said that more than two million flowers are reserved in refrigerators and cannot be delivered to the European markets because Kerem Shaloom crossing has been closed since Wednesday by Israel authorities due to security concerns.

"The flowers and those still not harvested would shrivel," the society warned in a statement.

Mahmoud Khlail, the head of the farmers' society, said that 30 million flowers were supposed to be shipped to Europe this spring, but so far only 10 million roses were exported. "The revenues does not cover costs, including shipping fees and payments for workers, " he said.

He noted that 1.5 million flowers have already been spoiled.

Kerem Shalom is the only crossing Israel allows currently to deliver goods, mainly food and consumer products, to the Gaza Strip.

Before Israel imposed a siege on Gaza in 2007, there had been four commercial crossings allowing the flow of goods.

Israel relaxed the blockade in June 2010 to ease international criticism after its commandos killed nine pro-Palestinian activists on an aid flotilla bound for Gaza.

Expecting a good season after Israel allowed the export of flowers and strawberries, Zakareya Hijjazi sealed a deal with a Greek importer and the first shipment of Hijjazi's flowers was supposed to leave on Thursday. "The Greek merchant calls me everyday, asking when I'm going to ship the carnation flowers," he said.

Although calm has prevailed for three days in Gaza after a deadly wave of cross-border violence that killed 19 Palestinians, the crossing remains closed.

The escalation started Thursday, when militants in Gaza fired a rocket at an Israeli school bus behind the border in southeast Gaza Strip, wounding a 16-year-old Israeli student.