The Hamas leadership has left its longtime base in Syria because of the regime's crackdown on opponents there, the No. 2 in the Islamic militant movement said in an interview Sunday at his new home on the outskirts of Cairo.

Moussa Abu Marzouk also told The Associated Press that a unity deal between Hamas and its political rival, Palestinian President Mahmoud Abbas, faces steep obstacles despite optimistic assessments made by both sides in public.

A unity deal reached earlier this month in Doha, Qatar, was meant to end more than four years of separate Palestinian governments _ one run by Hamas in the Gaza Strip and the other by the Western-backed Abbas in the West Bank. As part of the deal, Abbas was to lead an interim unity government ahead of general elections.

However, a series of meetings in Cairo this week among Palestinian politicians, including Abbas and Hamas chief Khaled Mashaal, did not bring the sides closer to setting up such a government, participants said.

In recent months, Hamas has increasingly drifted away from longtime patrons Iran and Syria, in part because of Syrian President Bashar Assad's bloody campaign against regime opponents. At the same time, Hamas has moved closer to its parent movement, the pan-Arab Muslim Brotherhood, which scored political gains from the uprisings of the Arab Spring and has tried to position itself as open-minded to widen its voter appeal.

Still, Hamas officials long played down reports of the movement's exodus from Syria.

Abu Marzouk noted Sunday that Hamas still has offices in Syria, but acknowledged that "practically, we are no longer in Syria because we couldn't practice our duties there."

Abu Marzouk has moved to a cottage on the outskirts of Cairo where he uses the second floor as an office. Previously, under the Israeli and Egyptian embargo on the Gaza Strip, only those with Gaza residency could live there, and many top Hamas leaders lived outside of the small, coastal enclave.

He said Mashaal and his aides have moved to Doha. Another Hamas official said this week that Mashaal twice turned down recent requests to meet with Assad and eventually decided to leave Syria.

"Our position on Syria is that we are not with the regime in its security solution, and we respect the will of the people," Abu Marouk said.

He said Hamas wants to keep its ties with Iran, but stood up to Tehran in refusing to side with Assad. "The Iranians are not happy with our position on Syria, and when they are not happy they don't deal with you in the same old way," he said, referring to a drop in Iranian aid to Hamas. He would not say how much money Hamas receives from Iran.

Abu Marzouk also said the Palestinian unity deal appears in trouble. Abbas told Mashaal this week that he does not want to form a unity government unless he has assurances that Israel will not block elections in east Jerusalem, the Israeli-annexed sector the Palestinians want as their future capital.

It appears unlikely Israel's government would permit campaigning in east Jerusalem, one of three war-won territories that, along with the West Bank and Gaza, is to make up a Palestinian state.

The interim government is to be made up of politically independent technocrats acceptable to both sides _ a constellation meant to enable Abbas to win international support for it. The West shuns Hamas as a terror organization and it's not clear whether it would deal with a government that has the Islamists' tacit support.

Abbas insists that the interim government adopt his nonviolent political program, while Hamas argues the government should have no political program at all since it will be short-lived, Abu Marzouk said.

Hamas also wants the government to be sworn in by and be accountable to the outgoing Hamas-dominated parliament, defunct since the violent Hamas takeover of Gaza in 2007, but Abbas refuses to accept that, Abu Marzouk said.