Users get blocked when access same table while getting Unique IDs

--Table which will have the Unique IDs

CREATE TABLE dbo.CounterTable

(

Counter int IDENTITY(1,1) NOT NULL

)
GO
--Procedure which Inserts unique IDs in table and returns the New ID

CREATE PROCEDURE dbo.GetNextCounter

AS

BEGIN TRAN

DECLARE @Counter BIGINT

INSERT INTO dbo.CounterTable DEFAULT VALUES

SET @Counter = SCOPE_IDENTITY()

COMMIT

RETURN @Counter

GO

--Now Use the @Counter to give each user the Unique ID

DECLARE @Counter int

EXEC @Counter = dbo.GetNextCounter

SELECT @Counter