WASHINGTON - The US should continue supporting Ukraine, former vice-president Mike Pence and New Hampshire Governor Chris Sununu said on Saturday, a position that puts them at odds with the top two contenders for the Republican presidential nomination.

Foreign policy has emerged as the main ideological fissure within the Republican Party as the 2024 nominating contest heats up.

While former president Donald Trump and Florida Governor Ron DeSantis have called for dedicating resources to domestic issues rather than Ukraine, several other declared and likely presidential candidates have portrayed themselves as unwavering defenders of the eastern European country.

Both Mr Pence and Mr Sununu have defended Ukraine before, but their Saturday comments were particularly pointed and come as the Republican foreign policy feud intensifies.

This week, Mr DeSantis said in a statement provided to conservative radio host Tucker Carlson that the war in Ukraine was a “territorial dispute,” which was not a vital national interest to the US.

Mr DeSantis has not declared a presidential run, but he is widely expected to do so, and he is by far Mr Trump’s most formidable Republican opponent.

Speaking in Iowa, Mr Pence, who is also expected to run, took a jab at the Florida governor.

“I must tell you the war in Ukraine is not a territorial dispute. It is a Russian invasion,” he told a group of Republicans near Des Moines.

“I truly do believe that this is a moment of testing for the free world to ensure peace in eastern Europe.”

Mr Pence did not criticise Mr Trump, even as the former president opposes dedicating more resources to Ukraine and once called Russian President Vladimir Putin a “genius” for invading the neighbouring country.

In a Washington Post opinion column, Mr Sununu, the New Hampshire governor, went a...