President Barack Obama has said G7 leaders will discuss “standing up to Russian aggression” in Ukraine, as he arrived at the summit in Germany.
Trade, violent extremism and climate change would also feature, he said.
The annual summit of leading Western economic powers is taking place in the Bavarian Alps.
Russia has been excluded from what was previously known as the G8, since the annexation of Crimea last year. It backs rebels in eastern Ukraine.
Ukraine Crisis to Dominate
There are concerns that President Vladimir Putin is d deliberately building up further military pressure in Ukraine, and Russia already faces sanctions imposed by the US and European countries.
The West accuses Russia of sending military forces into eastern Ukraine to help the rebels – a charge echoed by analysts. Moscow denies this, saying any Russian soldiers there are volunteers.
Germany, Britain and the US want an agreement to offer support to any EU member state tempted to withdraw backing for the sanctions on Moscow, which are hurting the Russian economy.
UK Prime Minister David Cameron said he was hopeful that there would be a united front to ensure that sanctions were “rolled over” despite admitting that “sanctions are having an impact on all of us”.
EU sanctions are due to expire at the end of July.Russian President Vladimir Putin said on Saturday that Russia was not a threat and had “other things to worry about”.
But, when asked if the US should redeploy intermediate-range nuclear missiles in Europe, Mr Hammond said the West had a “delicate act to perform”.
“We’ve got to send a clear signal to Russia that we will not allow them to transgress our red lines. At the same time we have to recognise that the Russians do have a sense of being surrounded and under attack, and we don’t want to make unnecessary provocations.”
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