The United States urged Russia to pull back from the brink over Ukraine, warning that the G 7 and its allies will impose tough measures if it abandons diplomacy.
A senior State Department official told reporters at a meeting of the group's top diplomats in Liverpool, northwest England, that Moscow still had time to change course.
The G 7 is absolutely united in that if they choose not to pursue that path, there will be massive consequences and severe costs in response, and the G 7 will be absolutely united in that, the official said.
They added that a large number of democratic countries will join us in imposing costs.
Russian sabre-rattling against Ukraine and how to counter an increasingly assertive China dominated the first day of a two-day meeting of G 7 foreign ministers in the British city.
The meeting at which ministers want to present a united front against authoritarianism is the last in-person gathering of Britain's year-long G 7 presidency, before it hands the baton to Germany.
Britain's Foreign Secretary Liz Truss told delegates: We need to come together strongly to stand up to aggressors who are trying to limit the bounds of freedom and democracy.
We need to have a united voice to do this. We need to expand our economic and security posture around the world. In September, Truss set out her foreign policy vision in a major address on Wednesday, echoing US threats of unprecedented sanctions if Russia invades Ukraine.
Western concerns are growing over a Russian troop build-up on the border that the Kremlin says is defensive against any move by the former Soviet state towards NATO.
The G 7 ministers want to show that the grouping can move beyond condemnation to defend its values as a deterrent to future threats.
The meeting comes after U.S. President Joe Biden held a virtual summit with Russian counterpart Vladimir Putin this week to try to end the stand-off.
Karen Donfried, Washington's top diplomat for Europe and Eurasian affairs, is headed to Kiev and Moscow next week for follow-up talks with senior government officials.
She will go to Brussels for further discussions with NATO and EU allies.
US Secretary of State Antony Blinken flies on to southeast Asia next week on a visit designed to highlight the region's importance in Washington's push for peace, security and prosperity in the Indo-Pacific region against China.
Britain's G 7 presidency has been dominated by a number of domestic rights abuses, as well as creeping authoritarianism in its former colony, Hong Kong.
A panel of human rights lawyers and experts in London concluded this week that China had committed genocide by imposing population restrictions, including birth control and forced sterilization on its Muslim minority Uyghurs.
Biden has pushed the G 7 for a stronger collective stance towards both Russia and China, and this week Washington, London and Canberra have announced diplomatic boycotts of the 2022 Beijing Winter Olympics.
In Liverpool delegates want to end the dependence of a growing number of low and middle-income countries on the G 7's adversaries in various areas from energy to technology.
The foreign office said that the foreign office said that the countries are being pushed to provide more funding for infrastructure and technology projects.
It said that the G 7 countries and their allies must offer an alternative to unsustainable debt from non-market economies like China.
Ministers from the Association of Southeast Asian Nations ASEAN will come to the G 7 summit for the first time on Sunday, in a session geared for wide-ranging talks on issues including Covid 19 vaccines, finance and gender equality.
South Africa, Australia, South Africa and India will also take part in Britain's chosen G 7 guests, with many attendees taking part virtually due to the Pandemic and the emergence of the Omicron variant.
Truss wants deeper ties between G 7 nations in trade, investment, technology and security to defend and advance freedom and democracy across the world. She will also unveil a UK-led initiative to invest in Africa's most fragile markets and develop a pipeline of investable opportunities.