Fears of a 'no deal' Brexit that experts have warned would be 'catastrophic' for the environment receded last night, after the EU offered the UK a new departure date of 31 October.

The extension to Article 50 was shorter than had been widely expected following marathon talks between the leaders of the EU27, which saw French President Emmanuel Macron oppose calls for a longer Brexit delay of nine to 12 months.

Voicing fears the UK could use the extension to disrupt the operation of the EU - as some leading Brexit campaigners have proposed - Macron forced a compromise agreement that resulted in a new proposed exit date of Halloween with a review of progress in June.  

"This extension is as flexible as I expected and a little bit shorter than I expected but it is still enough to find the best possible solution," European Council president, Donald Tusk, told reporters early this morning. "Please do not waste this time."

British Prime Minister Theresa May accepted the new plan and ducked questions about her future, having previously hinted she could not countenance a long extension and remain as Prime Minister. May will address the Commons this afternoon, where she can once again expect to face growing calls to step down.

The new agreement - which revealed sharp divisions between France and the rest of the EU during maraton six hour talks - leaves open the prospect of a wide range of scenarios for the green economy.

The extension means companies will remain subject to EU policies and regulations, including the EU emissions trading scheme, for longer than planned. It also significantly reduces the chances of a 'no deal' Brexit that would have resulted in economic disruption, new trade barriers, and fresh calls for deregulation.

However, it remains unclear if the UK will now leave the EU at the end of October, at the start of June, or end up seeking a further extension or cancelling Brexit altogether. 

Tusk indicated the EU27 could yet consider a further extension request.

It is also unclear if the UK will take part in the upcoming European elections, where Remain-backing parties such as the Greens and Leave-demanding parties such as Nigel Farage's new Brexit party will be hoping for a strong showing.

May last night reiterated her calls for MPs to back the government's Withdrawal Agreement so that the UK could avoid taking part in the European Parliament elections and depart the EU in June.

The government is now expected to continue its cross-party talks with Labour in an attempt to thrash out an agreement that could secure a majority in the Commons. 

The talks to date are understood to have touched on environmental issues with Environment Secretary Michael Gove providing a presentation on the government's 'Green Brexit' plans earlier this week. The government has repeatedly insisted it will deliver world-leading environmental standards post-Brexit, alongside a new green watchdog and wide-ranging agricultural reforms. But campaigners have warned the plans are not advanced enough and fear that a proposed US trade deal or change of leadership could quickly result in UK environmental rules being eroded. 

Labour has repeatedly signalled that stronger assurances on future environmental protections are essential if it is to back the Withdrawal Agreement. The opposition wants to see clearer commitments environmental standards will be maintained, including pledges for dynamic alignment with EU regulations and a clearer plan for the UK's continued engagement with EU agencies such as the European Chemicals Agency.

The cross-party talks are on-going, but Labour figures have complained that the government is yet to propose any meaningful changes to a deal that has already been rejected three times by Parliament.

If the cross-party talks break down the government has signalled it could orchestrate a new series of indicative votes to try and identify whether a new form of Brexit could secure a Commons majority.

With the last round of votes seeing strong backing for various forms of 'Soft Brexit', as well as a confirmatory referendum - albeit with no single plan securing a majority - a new wave of votes in which Cabinet Ministers could participate could yet result in a breakthrough and deliver a form of Brexit that incorporates stronger environmental protections and closer alignment with EU rules. 

However, the entire process is set to operate against a febrile political backdrop with Brexit-backing Cabinet Ministers insisting they cannot support a softer form of Brexit or second referendum and calls growing for May's resignation from all sides.