A US official has said if European allies use Huawei in future fifth generation (5G) networks the US will have to reassess its ability to share information with them.

Speaking during an online press briefing, Deputy Assistant Secretary for Cyber and International Communications and Information Policy at the Department of State Robert Strayer said the threat posed by the use of such equipment represents a "loaded gun".

Even using Huawei in non-core parts of 5G networks is a risk, he said, but added that the concerns are focused on security and not trade.

Mr Strayer said the US wants to maintain a secure cyberspace for future generations.

He said it and its partners recognise that cyber policy issues are critical to not just protecting communications networks, but also to national security, human rights and economic prosperity around the world.

Mr Strayer added that given the future transformative power of 5G that will touch every aspect of our lives, the stakes for security could not be higher.

As a result, the official said, the US is urging countries to adopt a risk-based security framework, an important element of which is a careful evaluation of supply chain and equipment vendors.

Suppliers who are subject to unchecked or extra-judicial control by a foreign power should be excluded as they could be ordered to undermine network security, skim personal information, conduct espionage, distribute cyber attacks and disrupt critical infrastructure, he claimed.

"A significant cause for concern are a number of Chinese laws that compel their companies to co-operate with intelligence and security services without independent judicial controls," he said.

He said many countries are following the US in acknowledging the supply chain risk by strengthening their ICT security.

Asked about reports that the UK had decided to allow limited use of Chinese manufactured equipment in its networks, Mr Strayer said the UK has not announced a final decision.

He said the UK, like many other countries, is on a path of conversation about its 5G networks.

Mr Strayer said it was premature to say whether co-operation between the US and other countries like the UK would be hindered by such a move, but added that disruption to services between the US and Europe would impact all of us.

"If other countries insert and allow untrusted vendors to build out and become the vendors for their 5G networks, we will have to reassess the ability for us to share information and be interconnected with them in the way we are today," he stated.

The intent, capabilities and opportunity combined provide a "loaded gun" to China, he added.

"It is something that western democracies who value human rights should think very carefully about if they want to give that to an authoritarian regime with very different values about uses of data," he said.

The official said the US thinks the EU Commission's recommendation to members to do assessments of risk by the end of June and then come up with an overall policy is an important first step.

But he said it will be borne out in how the standards and evaluations emerge in the months ahead.