HANOVER, Germany, April 25 (Reuters) - President Barack Obama announced on Monday the biggest expansion of U.S. ground troops in Syria since its civil war began, but the move was unlikely to mollify Arab allies angry over Washington's cautious approach to the conflict.
The deployment of 250 Special Forces soldiers increases U.S. forces in Syria roughly six-fold and is aimed at helping local militia fighters build on victories in which territory has been clawed back from Islamic State.
Defense experts said giving more fighters on the ground access to U.S. close air support could shift momentum in the war. But a senior member of the Saudi royal family who asked not to be identified dismissed the decision as "window dressing."
In announcing the deployment, Obama trumpeted the gains made on the ground against Islamic State.
"Given the success, I've approved the deployment of up to 250 additional U.S. personnel in Syria, including Special Forces, to keep up this momentum," Obama said in a speech in the German city of Hanover on the last stop of a foreign tour that has taken him to Saudi Arabia and Britain.
"They're not going to be leading the fight on the ground, but they will be essential in providing the training and assisting local forces as they continue to drive ISIL back," he added, using an acronym for Islamic State, also known as ISIS or Daesh.
The U.S. military has led an air campaign against Islamic State since 2014 in both Iraq and Syria, but its effectiveness in Syria has been limited by a lack of allies on the ground in a country where a complex, multi-sided civil war has raged for five years.
A Russian air campaign launched in Syria last year has been more effective because it is closely coordinated with the government of President Bashar al-Assad, who is Moscow's ally but a foe of the United States.
U.S. efforts in Syria have come against the backdrop of rising tensions with Saudi Arabia and other Gulf Arab monarchies, which have privately criticized the Obama administration's security toward the region.
CLOSE AIR SUPPORT
Washington's main allies on the ground have been a Kurdish force known as the YPG, which wrested control of much of the Turkish-Syrian border from Islamic State. However, the alliance has been constrained because U.S. ally Turkey is deeply hostile to the YPG.
"Presumably these (extra U.S. forces) are going to assist our Kurdish YPG friends to widen and deepen their offensive against IS in northeastern Syria," said Tim Ripley, defense analyst and writer for IHS Jane's Defence Weekly magazine.
The deployment will include medical and logistics support personnel, officials said, and U.S. support for the American forces in Syria will be staged out of northern Iraq.
Their goal will be to help screen and equip Arab fighters who are seeking to join up with the majority Kurdish Syrian Democratic Forces. U.S. officials say Arab fighters will be crucial to future operations against Islamic State in traditionally Arab parts of Syria.
But Washington would still have to take a political decision to help the Kurds despite Turkish objections. Kurdish advances have largely stopped since February, with Turkey opposed to the Kurds taking more territory.
The Syrian Democratic Forces, a U.S.-backed coalition set up in October to unite the Kurdish YPG and some Arab allies, welcomed Obama's announcement but said it still wanted more help.
"Any support they offer is positive but we hope there will be greater support," SDF spokesman Talal Silo said. "So far we have been supplied only with ammunition, and we were hoping to be supplied with military hardware."
The HNC umbrella opposition, which represents groups opposed to Assad but not the Kurds, also welcomed U.S. forces helping rid Syria of the Islamic State "scourge," but said Washington should do more to fight Assad.
If the Kurds are given the green light to advance with American air support, the main short-term objective could be sealing off the last stretch of the border that is not held by the Kurds or the government, west of the Euphrates river.
That would deny Islamic State access to the outside world, but would infuriate Turkey, which regards the border as the main access route for other Sunni Muslim rebel groups it supports against Assad, and for aid to civilians in rebel areas.
THE RACE FOR RAQQA
U.S. Special Forces teams providing close air support could ultimately help the Kurds advance on Raqqa, Islamic State's main Syrian stronghold and de facto capital.
With German Chancellor Angela Merkel sitting in the audience, Obama also urged Europe and NATO allies to do more in the fight against Islamic State. The group controls Mosul in Iraq in addition to Raqqa and a swathe of territory in between, and has proven a potent threat abroad, claiming responsibility for major attacks in Paris in November and Brussels in March.
"Even as European countries make important contributions against ISIL, Europe, including NATO, can still do more," Obama said.
European countries have mostly contributed only small numbers of aircraft to the U.S.-led mission targeting Islamic State in Iraq and Syria.
Obama pledged to wind down wars in the Middle East when he was first elected in 2008. But in the latter part of his presidency he has found it necessary to keep troops in Afghanistan, return them to Iraq and send them to Syria, where at least 250,000 people have been killed in the civil war.
In Iraq, Islamic State has been forced back since December when it lost Ramadi, capital of the western province of Anbar. In Syria, jihadist fighters have been pushed from the city of Palmyra by Russian-backed Syrian government forces.
TALKS IN MELTDOWN, TRUCE IN TATTERS
But Washington's lack of allies on the ground has meant its role in Syria has been circumscribed. The entry of Moscow into the conflict last year tipped the balance of power in favor of Assad against a range of rebel groups supported by Turkey, other Arab states and the West, including the United States.
Washington and Moscow have sponsored a ceasefire between most of the main warring parties since February, which allowed the first peace talks involving Assad's government and many of his foes to begin last month.
However, those talks appear close to collapse, with the main opposition delegation having suspended its participation last week, and the ceasefire is largely in tatters. Islamic State is excluded from the ceasefire.
Obama, Merkel and the leaders of Italy, Britain and France called on the parties in the Syrian war to respect the agreement to cease hostilities and make peace talks work, the White House said in a statement after a meeting of the Western leaders in Hanover.
Fighting has increased in recent days near Aleppo, once Syria's largest city, now split between rebel and government zones. A monitoring group said 60 people had been killed there in three days of intense fighting, including civilians killed by rebel shelling and government air strikes.
The Syrian government's negotiator at the Geneva talks said a bomb hit a hospital near a Shi'ite shrine near Damascus, killing many innocent people and proving the government's enemies were terrorists.
(Reporting by Roberta Rampton and Andreas Rinke in Hanover, Jeff Mason, Kevin Drawbaugh, John Walcott and Phil Stewart in Washington, Michelle Martin in Berlin and Peter Graff in London; Writing by Noah Barkin and Peter Graff; Editing by Peter Millership, Giles Elgood and Paul Simao)