Northern Ireland's Democratic Unionist Party (DUP) said on Thursday it could not support the Brexit deal being proposed by Prime Minister Boris Johnson and the European Union.

"As things stand, we could not support what is being suggested on customs and consent issues and there is a lack of clarity on VAT," DUP leader Arlene Foster and deputy leader Nigel Dodds said in a statement.

"We will continue to work with the Government to try and get a sensible deal that works for Northern Ireland and protects the economic and constitutional integrity of the United Kingdom."

The support of the DUP, which backs Johnson's government, is crucial as some hardline Brexiteers in his party say they will be swayed by its stance on the most difficult part of any agreement, the Irish border riddle.

Johnson, who has no majority in the 650-seat parliament, needs 320 votes to get a deal ratified. The DUP have 10 votes. 

(Cover: DUP leader Arlene Foster speaks during a meeting about abolishing the Irish backstop during the Conservative Party annual conference in Manchester, Britain, September 29, 2019. /VCG Photo)