The UK will be left vulnerable without a new government strategy on emerging technologies, a parliamentary committee is warning.
A U-turn on using the Chinese company Huawei had left the government over-reliant on a small group of 5G technology suppliers, MPs said.
Its subsequent strategy to deal with this had been too vague and too late.
And the issue could be repeated in other areas such as quantum computing and artificial intelligence (AI).
5G mobile telecoms networks are being rolled out in the UK, with the hope they boost connectivity and economic growth.
But the House of Commons Science and Technology Committee found the process had been made more costly and delayed by the government's decision, last year, to remove Huawei equipment from the network because of concerns over security and US sanctions.
And only two other companies could supply the crucial technology, leading to fresh concerns about security and resilience.
The government's 5G Supply Chain Diversification Strategy proposes using technology based around open standards.
But the committee warned this was not a "silver bullet" and other options should be considered.
And it wants a more detailed plan in the next three months.
But 5G was not the only emerging technology of critical importance to the UK's future, the committee said.
And the problems with it were not a "one-off".
AI and quantum computing could also bring significant benefits and threats, especially with growing divergence from China.
And this required more work to avoid another "supplier squeeze".
The committee called for a risk assessment and action plan in the next year.
It wants the government to do more to actively manage research and development, driving the effort of industry and academia to meet long-term objectives.
And it said there was a need to co-operate more with like-minded countries, for instance on diversifying the telecoms market.
"A lack of strategic foresight in 5G has seen the UK become dependent on only two vendors for a crucial technology," Greg Clark, who chairs the committee, said.
"We must learn from this experience to avoid making our economy and security vulnerable from a lack of acceptable alternatives in emerging technologies."
"As technologies develop at an ever faster rate, more time must not be lost."