LONDON - British Prime Minister Boris Johnson said on Tuesday that restrictions imposed on businesses and people to stop the spread of COVID-19 could be in place for six months without major progress in areas such as vaccine and treatment development.

"We will spare no effort in developing vaccines, treatments, new forms of mass testing, but unless we palpably make progress we should assume that the restrictions I have announced will remain in place for perhaps six months," he told parliament.

(Reporting by Guy Faulconbridge and Estelle Shirbon; writing by Costas Pitas) ((Costas.Pitas@thomsonreuters.com; 02075428024; Reuters Messaging: costas.pitas.thomsonreuters@reuters.net and @Cpitas on Twitter))