Brussels - The European Union's executive is to summon international lenders to Brussels next week to discuss if they can help Ukraine pay for Russian gas destined for the EU, the head of the European Commission said Friday.

The Brussels-based body "intends to host a meeting next week with representatives of the international financial institutions, European gas companies and EU member states to look at whether a short-term package of 'stop-gap' funding can be put together," Jose Manuel Barroso said at the end of an EU summit in Brussels.

"In the medium term, we have to continue to probe for a sustainable solution which delivers gas reliably via this route," he said.

"We must not sleep-walk into another crisis. There is a risk of another crisis in weeks, not months," he warned.

Ukraine usually buys natural gas from Russian in the summer, stores it underground and sells it on to EU customers in the winter.

But under the impact of the current financial crisis, Ukrainian officials say they will need a loan of some 4.2 billion dollars to buy that gas - otherwise Europe will go cold this winter.

"The amount being requested does not exist in the EU budget," Barroso stressed.

In January, a row between Russia and Ukraine over allegedly unpaid bills led to two weeks of gas cut-offs across a swathe of Central and Eastern Europe. The warning that another crisis could come as soon as early July has alarmed EU members.

Friday's summit stressed that the EU "is convinced that all parties will honour their commitments," the leaders of the bloc's 27 member states said in a joint declaration.

But the EU is already pushing for the construction of new gas pipelines across Turkey to Azerbaijan and the Middle East, in a bid to reduce its reliance on Russian gas.

A quarter of the gas burned in the EU currently comes from Russia. Eighty per cent of it flows through Ukrainian pipelines.(dpa)