Building an East Mediterranean gas pipeline to Europe as an alternative to Russian energy would be too expensive and take too long to build, a senior US diplomat said Thursday.

The EastMed pipeline to transfer natural gas from Israeli waters to Europe via Cyprus and Greece was announced in 2016, and several agreements have been signed.

The three states aimed to complete the €6 billion ($6.5 billion) project by 2025, but no financing has been secured.

US State Department official Victoria Nuland said the pipeline was too long, in very deep waters and would take a decade to build.

"We believe it is too expensive, not economically viable and will take too long," Nuland said, after meeting Cypriot President Nicos Anastasiades.

"When we think about hydrocarbons, both in the US context and in the EU context, we are hoping for a quick transition -- and frankly, we don't have 10 years," she added.

"So what we are looking for within the hydrocarbon context are options that can get us more gas, more oil for this short transition period."

Greece, Cyprus and Israel signed a deal in January 2020 to build a 2,000-kilometre (1,250 mile) subsea pipeline.

Nuland said there was a need to search for alternative supplies to avoid dependence on Russian energy after Moscow invaded Ukraine.

"Countries throughout this area have understood that dependence on Russian oil and gas is an extremely bad bet," Nuland said.

"There is a convergence of interest in diversifying supply even as we work to get green."

She said Washington does support other projects that Cyprus, Greece and Israel are involved in.

That includes the €2.5 billion ($2.7 billion) EuroAsia Interconnector -- the world's longest and deepest underwater power cable, linking their electricity grids with Europe -- which is slated to be completed by 2025.

"We have supported the idea of the EuroAsia electricity interconnector and other projects," Nuland said.