Given the recent statement from the President of the USA, now would be a good opportunity for the UK to join the USA in recognizing Jerusalem as the Israeli Capital. To resolve the Palestine-Israel issue the UK Gov't must take steps which will pressure both sides to enter into proper negotiations.
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Statement by President Donald Trump - http://www.bbc.co.uk/news/world-us-canada-42259443
Prime Minister May's statement against recognizing Jerusalem as the Israeli Capital - https://www.gov.uk/government/news/pm-statement-on-us-decision-to-move-embassy-to-jerusalem-6-december-2017
Prime Minister Netanyahu's Response to President Donald Trump's Statement -http://www.pmo.gov.il/English/MediaCenter/Spokesman/Pages/spoke_statement061217.aspx