Iran is helping terrorists in Gaza prepare for war with Israel, according to a leading Hamas official.

"Every day we build missiles and continue military training," Yahya Sinwar, a military leader recently voted prime minister of Hamas in Gaza, told reporters.

That effort derives significant support from Iran.

"The Iranian military support to Hamas and al-Qassam [the military wing of Hamas] is strategic," Sinwar said, per the Times of Israel.

Their renewed cooperation shows that Hamas and the Iranians have patched up a relationship that deteriorated when they disagreed over support for Syrian dictator Bashar Assad. It also points to how Assad and Iran's wins in Syria strengthens Israel's terrorist enemies.

Iran has long supported Palestinian terrorist groups as well as Hezbollah, a Lebanese terrorist group that controls territory north of Israel. Sinwar's comments bolster concerns that U.S. officials and Congressional observers have had about the conflict in Syria. Although most public discussions about the Syria crisis have focused on the threat of the Islamic State, or Assad's willingness to use chemical weapons against his own people, major world powers have seen a subtler long-term significance to the outcome of the conflict.

Russia and Iran have partnered to support Assad, who had been weakened by the combined threats of U.S.-backed rebels and the radical terrorists who formed the ISIS caliphate. With their help, Assad has recaptured rebel-held territory, while the United States has focused on the defeat of ISIS.

"Assad has won and he will stay [in power]," former U.S. ambassador to Syria Robert Ford told The National, an Australian paper, in a new interview. "He may never be held accountable, and Iran will be in Syria to stay. This is the new reality that we have to accept, and there isn't much we can do about it."

Russia has received, through Assad, access to a naval base on the Mediterranean. But Russian President Vladimir Putin's team has also worked to help Iran control land in Syria that will allow them to provide more supplies to terrorists in Lebanon.

"The coming period will witness military cooperation at a high level between Syrian and Iraqi government forces and their supporting units… made possible through Iranian military experts and in collaboration with the Russian air force in order to support the forces of the Syrian regime," a Russian military base announced in May, according to Foreign Affairs. "Apart from securing the highway connecting Damascus and Baghdad, this military campaign will be a race with the armed opposition, which is planning on establishing a buffer zone next to the Golan Heights and the Jordanian-Iraqi border with direct American support."

The Golan Heights is strategically important region that Israel captured from Syria in the 1967 Six-Day War.

Such reports have alarmed U.S. foreign policy leaders. "One of my highest concerns is the Iranians' ability to get a land bridge out to the Mediterranean to increase their logistical support for terrorist networks," House Intelligence Chairman Devin Nunes told the Washington Examiner in June. "You've got the largest state sponsor of terrorism, Iran -- if they get the logistical capability to move massive amounts of weapons and equipment and God knows what else quickly to the west, it's a real danger."

That was the context for Israeli Prime Minister Benjamin Netanyahu's opposition to Russia guaranteeing the stability of a ceasefire in southern Syria. But President Trump's team agreed to that demand.

"If [the Iranians] begin to build infrastructure which might be used against Israel in Syria and will connect this land corridor into Iraq and begin to move materials from this area into Syria, that will make the war inevitable," Yaakov Amidror, who counseled Netanyahu from 2011 to 2013, told reporters on a conference call hosted by The Israel Project.

Sinwar maintained that Hamas isn't looking for war in the near future, despite their determination to win "the liberation of Palestine" long-term. "[Hamas] takes every effort to avoid a war," he said. "At the same time we are not afraid of a war and are ready for it."