Russia and the United States' top diplomats have said their governments have failed to find a solution on the crisis in the Ukraine region of Crimea, following six hours of last-ditch talks.

Following talks on Friday in London, the Russian foreign minister, Sergey Lavrov, said that Russia would respect the "will of the Crimean people" and the result of a referendum on joining Russia, being held on Sunday.

Lavrov said that Russia and the US did not share a "common vision" on Ukraine and no solution had been forthcoming.

"The crisis in Ukraine is not the result of Russia's actions ... [Russia] will respect the will of the Crimean people during the referendum on March 15," said Lavrov.

He added that Russia had no plans to invade other areas of Ukraine. Ukraine has reinforced regions bording Crimea in the past few days.

John Kerry, the US secretary of state, later said that he had presented "constructive ideas" that respected Ukraine's integrity while addressing Russia's concerns, but Lavrov said he would not make Russia's position clear until after the referendum was held.

Kerry said the referendum was a violation of Ukraine law and its result would not be recognised by the US and its allies.

Al Jazeera's Simon McGregor-Wood, reporting from London, said that the result of Friday's talks showed that "the ball is very much in President Putin's court".

"If, for example, he takes a 'yes' vote from the referendum and rubber stamps it at the Kremlin, Kerry will consider that as a backdoor annexation. And if that's the case, that will escalate the tension to a much more serious level than it already is," said our correspondent.

Pro-Russian forces seized control of the region following a coup earlier this month in the capital Kiev, which removed the pro-Russian president, Viktor Yanukovich.

The US has submitted a draft resolution to the UN Security Council condemning Russia's actions in Crimea, aiming to gain support from other members to isolate Moscow internationally.

Meanwhile, the Reuters news agency reported that the Russian president, Vladimir Putin, told the UN chief, Ban Ki-moon, that the decision to hold a referendum on Crimea's status is completely in line with international law.

Putin's comments on Friday came shortly after his US counterpart, Barack Obama, said he continued to hope for a diplomatic solution, but warned of "consequences" for Russia if none is found.

"The United States and Europe stand united not only on (the) message about Ukrainian sovereignty, but also that there will be consequences if in fact that sovereignty continues to be violated," Obama said.

PHOTO CAPTION

Armed men, believed to be Russian servicemen, walk outside a Ukrainian military base in Perevalnoye, near the Crimean city of Simferopol, March 14, 2014

Al-Jazeera