British Prime Minister David Cameron attends the opening session of the Nuclear Security Summit in The Hague March 24, 2014. REUTERS/Sean Gallup/Pool

THE HAGUE (Reuters) - The Group of Seven big economies should cancel a meeting with Russia in June, British Prime Minister David Cameron said on Monday, as Western leaders prepared to discuss their response to Russia’s annexation of Crimea.

“We should be clear there’s not going to be a G8 summit this year in Russia. That’s absolutely clear,” Cameron told reporters during the nuclear security summit in The Hague.

Cameron was speaking ahead of a hastily-convened meeting with other leaders of the G7 - a group of industrialised nations that excludes Russia, which joined in 1998 to form the G8.

The G7 has already suspended preparations for a G8 summit scheduled to be held in Russia’s Black Sea resort of Sochi in June.

In the biggest East-West confrontation since the Cold War, the United States and the European Union have imposed visa bans and asset freezes on some of Russian President Vladimir Putin’s closest political and business allies.

But they have held back so far from measures designed to hit Russia’s wider economy.

Asked about a build-up of Russian forces along the Russia-Ukraine border, Cameron said any further incursions by the Russian military would trigger a fresh wave of sanctions.

“These reports are concerning and we need to send a very clear message to the Russian government and to President Putin that it would be completely unacceptable to go further into Ukraine, and that would trigger sanctions from the EU, from the U.S., from other countries as well,” Cameron said.