MEPs were quick to react after the commission outlined plans for an energy union last week.
Martin Schulz, president of the parliament, was broadly supportive, saying, "the energy union is needed to reinforce the EU's stance ahead of the December Paris climate conference", adding that "current events highlight the urgency for the EU to increase energy security".
Jerzy Buzek, chair of parliament's industry, research and energy committee, commented, "an internal energy market with an excellent level of interconnection and without isolated 'energy islands' will enable us to help each other, guaranteeing energy supply to all regions".
The former parliament president noted that "stable, sustainable, affordable and competitive energy is a challenge which no EU member state is capable of meeting by itself".
He also stressed that "developments in relations with Russia might have been an impulse for us to shift up a gear in our energy considerations, but altering the EU's relations with Russia or any other party is not one of the energy union's goals".
Representatives from the S&D group also appeared quite happy with the commission's energy union plans. The Socialists' spokesperson on climate and environment, Matthias Groote, said, "the paper on the energy union represents a first step towards a sustainable, decarbonised economy in Europe".
Dan Nica, the group's spokesperson on energy, praised them as "a good balance between the geostrategic need to reduce our energy dependency on expensive imports and the fair demand from families and industries to reduce the price of energy".
"An ambitious energy union will not only create jobs, growth and tackle climate change, it will also hit Putin where it hurts most" - Guy Verhofstadt
Meanwhile, the Liberals were especially vocal on the proposal's foreign policy aspects. ALDE group president Guy Verhofstadt highlighted that "an ambitious energy union will not only create jobs, growth and tackle climate change, it will also hit Putin where it hurts most".
He added, "Europe can no longer afford its addiction to imported fossil fuels from Russia and the Middle East. Our dependence on external energy resources has affected our ability to conduct an independent foreign policy. It is time for a European energy union with teeth".
And the group's environment, public health and food safety committee coordinator Gerben-Jan Gerbrandy warned, "the true test of the energy union will be overcoming the current fragmentation of energy policy into 28 different systems and reaping the full benefits of a common European approach".
Morgen Helveg Petersen, a vice-chair of parliament's industry, research and energy committee, underlined that "investors will only put their money in the many projects of the energy union if the associated regulatory framework is put in place, environmental legislation is predictable and competition policy is sound. The biggest barrier is regulatory uncertainty - we need to fix that".
Yet not everyone was impressed with the energy union plans. Marek Gróbarczyk, ECR group spokesperson on energy, called on council president Donald Tusk to "stick to the promises that he made - to build a real, coherent energy union including ‘gas solidarity’, rehabilitation of coal and substantial diversification".
In his view, "these proposals are disappointing because I fear they offer a virtual energy union that is not adequate to meet our growing challenges".
"If the EU wants to get serious about energy security, it should be prioritising energy efficiency as the first line of defence" - Claude Turmes
Over on the left, MEPs were equally cynical.
Greens/EFA energy spokesperson Claude Turmes criticised the commission's proposals as "a missed opportunity for outlining a path to a real energy transition in Europe. The overarching focus is on finding new supply routes for gas and reviving nuclear power, rather than trying to wean us off our damaging dependence on unreliable energy exporters. If the EU wants to get serious about energy security, it should be prioritising energy efficiency as the first line of defence".
Greens/EFA vice-chair Bas Eickhout pointed out that the proposed strategy "will not create the energy system we need to stop climate warming greenhouse gases and limit the increase in global temperatures to below two degrees, which is necessary to prevent catastrophic climate change".
GUE/NGL group member Josu Juaristi was also wary of the commission's announcements, explaining that, "in some member states investment in renewables is almost disappearing. Very little account is taken of citizens or local government. What happens is that the big energy companies' control over our citizens is strengthened.
"We need to avoid a situation where the EU just leaves its ideas for renewable energy on paper - as we see happening at the moment", he concluded.
The energy union is due to be discussed at this week's council summit.