U.S. Secretary of State Clinton said that Washington and Turkey will expand “detailed operational planning for Syria,” in a press conference in Ankara on Saturday.

Clinton said the latest sanctions against Syria’s ally Hezbollah was needed to put forth more pressure against the regime of President Bashar al-Assad.

She said Syrian activists have requested U.S. support to face Assad regime’s more powerful military.

Meanwhile, Turkish Foreign Minister Ahmet Davutoglu said that a U.N. support is needed to end Syrian conflict and that discussions with Clinton have focused on a post-Assad era. Davutgolu warned that Assad’s air forces are committing massacres in the northern city of Aleppo.

Clinton arrived Saturday in Istanbul for talks on the conflict in Syria with Turkish leaders after Washington slapped fresh sanctions on Assad’s regime and its allies.

Clinton flew in after wrapping up a nine-nation Africa tour.

The visit comes after Washington on Friday announced sanctions on Syrian state oil company Sytrol for trading with Iran, in a bid to starve the regimes in both Tehran and Damascus of much-needed revenue.

The U.S. Treasury also said it was adding the Lebanese Shiite militant group Hezbollah, which has close ties with Iran and Syria, to a blacklist of organizations targeted under Syria-related sanctions.

Washington already classes Hezbollah a “terrorist organization” and it is under U.S. sanctions, but Friday’s move explicitly ties the group to the violence in Syria, where Assad is attempting to put down a 17-month revolt.

The sanctions are designed to increase pressure on the Assad regime as the conflict escalates sharply after the failure of former U.N.-Arab League envoy Kofi Annan’s peace plan and his dramatic resignation.

What is expected from talks?
In Istanbul, Clinton will have “lengthy and in-depth conversation” with Turkey’s president, prime minister and foreign minister to discuss a three-pronged strategy, a U.S. official said.

The first aspect is “how we judge the effectiveness of what we are doing in terms of supporting the opposition,” the official said, adding that pressure and isolation of the regime was part of the strategy.

Clinton is expected to discuss with Turkey’s leaders ways to effectively enforce sanctions against Damascus.

Turkey, once a close ally of Syria, has become a vocal opponent of the regime since it launched a brutal crackdown on dissent in March last year.

Relations hit an all-time low after a Turkish fighter jet was shot down by Syrian fire in June, killing its two-man crew and leading Ankara to brand Damascus a “hostile” opponent.

In November, the Turkish government joined Arab League sanctions, freezing Syrian government financial assets, imposing a travel ban on senior Syrian officials and cutting off transactions with the country’s central bank.

The second part of the strategy, according to the U.S. official, would be to extend humanitarian assistance to Turkey as it copes with an influx of refugees from Syria.

Clinton to give Syrians aid
In Istanbul, Clinton is expected to announce an additional $5.5 million in aid for those fleeing fighting that monitoring groups say has now claimed over 21,000 lives.

Turkey is currently home to more than 50,000 refugees living in camps along the Syrian border.

This week has seen a marked increase in refugees, with close to 10,000 turning up at the border amid intensifying battles between regime forces and rebels for Syria’s second city of Aleppo.

The third strategy, the U.S. official said, is built on a transition plan out of the “strong conviction” that Assad’s days are numbered and that the international community needs to be prepared to support Syrians.

U.S. President Barack Obama and Turkish Prime Minister Recep Tayyip Erdogan agreed at the end of July to work on political change in Syria, including Assad's departure.

Turkey is also providing sanctuary to forces defecting from Assad's army to link up with the opposition Free Syrian Army, some of whose leaders are based on Turkish soil near the border.

Clashes between Jordan and Syria
In a related story, fighting broke out between Jordanian and Syrian forces in a border region between the two countries late on Friday, but a Jordanian source said no one on Jordan’s side appeared to have been killed.

It was the most serious incident between the two countries since the uprising in Syria against Syrian leader began 17 months ago.

A Syrian opposition activist who witnessed the fighting said armored vehicles were involved in the clash in the Tel Shihab-Turra area, about 80 km (50 miles) north of the Jordanian capital Amman, that occurred after Syrian refugees tried to cross into Jordan.

“The Syrians fired into Jordan at 10.30 p.m. in pursuit of refugees and the Jordanians responded. The fighting escalated and Jordanian armored vehicles hit two Syrian border guard outposts,” said the activist, giving his name only as Abdallah.

“The fighting was intense for an hour and now it is intermittent,” he said.
A Jordanian source, speaking on condition of anonymity, said: “The Syrian side fired across the border and fighting ensued. Initial reports indicate that there has been no one killed from the Jordanian side.”

Tens of thousands of Syrians have crossed into Jordan since the start of the uprising.