NATO

Secretary-General Jens Stoltenberg said the costs of war were high, but the price of letting Moscow achieve its military goals was even greater.

UK Prime Minister Boris Johnson has also warned of a longer-term conflict.

And in a stark warning, the newly appointed head of the British Army said the UK and allies needed to be capable of winning a ground war with Russia.

The international security organisation's chief said the move would send a message to Russia that there are "costs and consequences" for its behaviour.

Twenty-six countries have expelled Russian envoys in the past two days, in solidarity with the UK.

They all believe Russia was behind the poisoning of two people in Salisbury.

Russian ex-spy Sergei Skripal and his daughter, Yulia, were poisoned on 4 March in the southern English city, and investigators say a military-grade nerve agent was used.

Russian has denied involvement.

In the largest buildup of troops in the region since the Cold War, the UK has said it will send Royal Air Force Typhoon jets to Romania for up to four months in 2017.

Defense Secretary Michael Fallon also confirmed that 800 personnel will be moved to Estonia, 150 more than originally planned.

"Backed by a rising defense budget, this deployment of air, land and sea forces shows that we will continue to play a leading role in NATO, supporting the defense and security of our allies from the north to the south of the alliance," Fallon said.

Multiple U.S. breakdowns may have led to the aerial pummeling.

At least three official investigations are underway, including a short-term NATO assessment that could open an early window into what went wrong. But on Wednesday, Doctors Without Borders, the international charity whose medical clinic was hit Saturday, called for an independent investigation, saying the attack was possibly a war crime and that U.S. and Afghan investigators cannot be relied upon to be impartial.

Turkey's military, meanwhile, said more of its jets patrolling the border with Syria were placed in a radar lock by Russian planes and surface-to-air missile systems.

In Syria, Russian warplanes reportedly continued pounding targets in the country, where the Kremlin has come to the aid of beleaguered ally President Bashar Assad.

U.S. warplanes carried out an early morning airstrike on Taliban positions, but government ground troops sent to try to retake Kunduz, one of Afghanistan's wealthiest and most strategic cities, were stalled by roadblocks and ambushes, unable to move closer than about a mile (two kilometers) toward their target.

A NATO officer said more airstrikes were unlikely as "all the Taliban are inside the city and so are all the people." He spoke on condition of anonymity because he was not authorized to brief media on the issue.

"Kunduz city has collapsed into the hands of the Taliban," Interior Ministry spokesman Sediq Sediqqi told the Associated Press.

The fall of Kunduz marks a major setback for government forces, who have struggled to combat the Taliban since the U.S. and NATO shifted to a supporting role at the end of last year.

Military reinforcements have been sent to Kunduz, where government forces managed to fend off a major Taliban assault earlier this year. "We are trying our best to clear the city as soon as possible," Sediqqi said.

The assault ships, which can each carry 16 helicopter gunships, 700 troops and up to 50 armored vehicles, were originally intended for Russia. France continued building to Russia's specifications — including stenciling Cyrillic writing throughout the vessels — until the deal finally fell apart because of the Ukraine crisis. It was originally supposed to be the biggest arms sale ever by a NATO country to Russia.

The 66-year-old, who strongly opposes the government's austerity policies and Britain's membership of NATO, was considered an outsider but in recent months became the runaway favourite over three more mainstream rivals to win Saturday.

Cheers and applause erupted in the London conference venue as it was announced that Corbyn won almost 60 percent of the vote, far ahead of his closest rival, Andy Burnham, who scored 19 percent. Some 422,664 votes were cast.